diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 4c9a98951fae8..59ce935546bf5 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -1453,6 +1453,12 @@ namespace ts {
                             location = location.parent;
                         }
                         break;
+                    case SyntaxKind.JSDocTypedefTag:
+                    case SyntaxKind.JSDocCallbackTag:
+                        // js type aliases do not resolve names from their host, so skip past it
+                        lastLocation = location;
+                        location = getJSDocHost(location).parent;
+                        continue;
                 }
                 if (isSelfReferenceLocation(location)) {
                     lastSelfReferenceLocation = location;
@@ -2153,25 +2159,31 @@ namespace ts {
          */
         function resolveEntityNameFromJSSpecialAssignment(name: Identifier, meaning: SymbolFlags) {
             if (isJSDocTypeReference(name.parent)) {
-                const host = getJSDocHost(name.parent);
-                if (host) {
-                    const secondaryLocation = getJSSpecialAssignmentSymbol(getJSDocHost(name.parent.parent.parent as JSDocTag));
-                    return secondaryLocation && resolveName(secondaryLocation, name.escapedText, meaning, /*nameNotFoundMessage*/ undefined, name, /*isUse*/ true);
+                const secondaryLocation = getJSSpecialAssignmentLocation(name.parent);
+                if (secondaryLocation) {
+                    return resolveName(secondaryLocation, name.escapedText, meaning, /*nameNotFoundMessage*/ undefined, name, /*isUse*/ true);
                 }
             }
         }
 
-        function getJSSpecialAssignmentSymbol(host: HasJSDoc): Declaration | undefined {
-            if (isPropertyAssignment(host) && isFunctionLike(host.initializer)) {
-                const symbol = getSymbolOfNode(host.initializer);
-                return symbol && symbol.valueDeclaration;
+        function getJSSpecialAssignmentLocation(node: TypeReferenceNode): Declaration | undefined {
+            const typeAlias = findAncestor(node, node => !(isJSDocNode(node) || node.flags & NodeFlags.JSDoc) ? "quit" : isJSDocTypeAlias(node));
+            if (typeAlias) {
+                return;
             }
-            else if (isExpressionStatement(host) &&
-                     isBinaryExpression(host.expression) &&
-                     getSpecialPropertyAssignmentKind(host.expression) === SpecialPropertyAssignmentKind.PrototypeProperty) {
+            const host = getJSDocHost(node);
+            if (host &&
+                isExpressionStatement(host) &&
+                isBinaryExpression(host.expression) &&
+                getSpecialPropertyAssignmentKind(host.expression) === SpecialPropertyAssignmentKind.PrototypeProperty) {
                 const symbol = getSymbolOfNode(host.expression.left);
                 return symbol && symbol.parent.valueDeclaration;
             }
+            const sig = getHostSignatureFromJSDocHost(host);
+            if (sig) {
+                const symbol = getSymbolOfNode(sig);
+                return symbol && symbol.valueDeclaration;
+            }
         }
 
         function resolveExternalModuleName(location: Node, moduleReferenceExpression: Expression): Symbol {
@@ -9554,7 +9566,16 @@ namespace ts {
                 // parameters that are in scope (and therefore potentially referenced). For type literals that
                 // aren't the right hand side of a generic type alias declaration we optimize by reducing the
                 // set of type parameters to those that are possibly referenced in the literal.
-                const declaration = symbol.declarations[0];
+                let declaration = symbol.declarations[0];
+                if (isInJavaScriptFile(declaration)) {
+                    const paramTag = findAncestor(declaration, isJSDocParameterTag);
+                    if (paramTag) {
+                        const paramSymbol = getParameterSymbolFromJSDoc(paramTag);
+                        if (paramSymbol) {
+                            declaration = paramSymbol.valueDeclaration;
+                        }
+                    }
+                }
                 let outerTypeParameters = getOuterTypeParameters(declaration, /*includeThisTypes*/ true);
                 if (isJavaScriptConstructor(declaration)) {
                     const templateTagParameters = getTypeParametersFromDeclaration(declaration as DeclarationWithTypeParameters);
diff --git a/src/compiler/utilities.ts b/src/compiler/utilities.ts
index 7339907547a57..6e440e01ecfbc 100644
--- a/src/compiler/utilities.ts
+++ b/src/compiler/utilities.ts
@@ -1865,8 +1865,7 @@ namespace ts {
             //   * @returns {number}
             //   */
             // var x = function(name) { return name.length; }
-            if (parent.parent &&
-                (getSingleVariableOfVariableStatement(parent.parent) === node)) {
+            if (parent.parent && (getSingleVariableOfVariableStatement(parent.parent) === node)) {
                 getJSDocCommentsAndTagsWorker(parent.parent);
             }
             if (parent.parent && parent.parent.parent &&
@@ -1913,8 +1912,11 @@ namespace ts {
         return parameter && parameter.symbol;
     }
 
-    export function getHostSignatureFromJSDoc(node: JSDocTag): SignatureDeclaration | undefined {
-        const host = getJSDocHost(node);
+    export function getHostSignatureFromJSDoc(node: Node): SignatureDeclaration | undefined {
+        return getHostSignatureFromJSDocHost(getJSDocHost(node));
+    }
+
+    export function getHostSignatureFromJSDocHost(host: HasJSDoc): SignatureDeclaration | undefined {
         const decl = getSourceOfDefaultedAssignment(host) ||
             getSourceOfAssignment(host) ||
             getSingleInitializerOfVariableStatementOrPropertyDeclaration(host) ||
diff --git a/tests/baselines/reference/paramTagTypeResolution.symbols b/tests/baselines/reference/paramTagTypeResolution.symbols
new file mode 100644
index 0000000000000..1584e2fcb95c6
--- /dev/null
+++ b/tests/baselines/reference/paramTagTypeResolution.symbols
@@ -0,0 +1,23 @@
+=== tests/cases/conformance/jsdoc/main.js ===
+var f = require('./first');
+>f : Symbol(f, Decl(main.js, 0, 3))
+>require : Symbol(require)
+>'./first' : Symbol("tests/cases/conformance/jsdoc/first", Decl(first.js, 0, 0))
+
+f(1, n => { })
+>f : Symbol(f, Decl(main.js, 0, 3))
+>n : Symbol(n, Decl(main.js, 1, 4))
+
+=== tests/cases/conformance/jsdoc/first.js ===
+/** @template T
+ * @param {T} x
+ * @param {(t: T) => void} k
+ */
+module.exports = function (x, k) { return k(x) }
+>module : Symbol(export=, Decl(first.js, 0, 0))
+>exports : Symbol(export=, Decl(first.js, 0, 0))
+>x : Symbol(x, Decl(first.js, 4, 27))
+>k : Symbol(k, Decl(first.js, 4, 29))
+>k : Symbol(k, Decl(first.js, 4, 29))
+>x : Symbol(x, Decl(first.js, 4, 27))
+
diff --git a/tests/baselines/reference/paramTagTypeResolution.types b/tests/baselines/reference/paramTagTypeResolution.types
new file mode 100644
index 0000000000000..daf7749c6bb84
--- /dev/null
+++ b/tests/baselines/reference/paramTagTypeResolution.types
@@ -0,0 +1,31 @@
+=== tests/cases/conformance/jsdoc/main.js ===
+var f = require('./first');
+>f : <T>(x: T, k: (t: T) => void) => void
+>require('./first') : <T>(x: T, k: (t: T) => void) => void
+>require : any
+>'./first' : "./first"
+
+f(1, n => { })
+>f(1, n => { }) : void
+>f : <T>(x: T, k: (t: T) => void) => void
+>1 : 1
+>n => { } : (n: number) => void
+>n : number
+
+=== tests/cases/conformance/jsdoc/first.js ===
+/** @template T
+ * @param {T} x
+ * @param {(t: T) => void} k
+ */
+module.exports = function (x, k) { return k(x) }
+>module.exports = function (x, k) { return k(x) } : <T>(x: T, k: (t: T) => void) => void
+>module.exports : any
+>module : any
+>exports : any
+>function (x, k) { return k(x) } : <T>(x: T, k: (t: T) => void) => void
+>x : T
+>k : (t: T) => void
+>k(x) : void
+>k : (t: T) => void
+>x : T
+
diff --git a/tests/baselines/reference/typedefTagTypeResolution.errors.txt b/tests/baselines/reference/typedefTagTypeResolution.errors.txt
new file mode 100644
index 0000000000000..8d8c324beb32f
--- /dev/null
+++ b/tests/baselines/reference/typedefTagTypeResolution.errors.txt
@@ -0,0 +1,37 @@
+tests/cases/conformance/jsdoc/github20832.js(2,15): error TS2304: Cannot find name 'U'.
+tests/cases/conformance/jsdoc/github20832.js(17,12): error TS2304: Cannot find name 'V'.
+
+
+==== tests/cases/conformance/jsdoc/github20832.js (2 errors) ====
+    // #20832
+    /** @typedef {U} T - should be "error, can't find type named 'U' */
+                  ~
+!!! error TS2304: Cannot find name 'U'.
+    /**
+     * @template U
+     * @param {U} x
+     * @return {T}
+     */
+    function f(x) {
+        return x;
+    }
+    
+    /** @type T - should be fine, since T will be any */
+    const x = 3;
+    
+    /**
+     * @callback Cb
+     * @param {V} firstParam
+               ~
+!!! error TS2304: Cannot find name 'V'.
+     */
+    /**
+     * @template V
+     * @param {V} vvvvv
+     */
+    function g(vvvvv) {
+    }
+    
+    /** @type {Cb} */
+    const cb = x => {}
+    
\ No newline at end of file
diff --git a/tests/baselines/reference/typedefTagTypeResolution.symbols b/tests/baselines/reference/typedefTagTypeResolution.symbols
new file mode 100644
index 0000000000000..9201ecb2cd855
--- /dev/null
+++ b/tests/baselines/reference/typedefTagTypeResolution.symbols
@@ -0,0 +1,38 @@
+=== tests/cases/conformance/jsdoc/github20832.js ===
+// #20832
+/** @typedef {U} T - should be "error, can't find type named 'U' */
+/**
+ * @template U
+ * @param {U} x
+ * @return {T}
+ */
+function f(x) {
+>f : Symbol(f, Decl(github20832.js, 0, 0))
+>x : Symbol(x, Decl(github20832.js, 7, 11))
+
+    return x;
+>x : Symbol(x, Decl(github20832.js, 7, 11))
+}
+
+/** @type T - should be fine, since T will be any */
+const x = 3;
+>x : Symbol(x, Decl(github20832.js, 12, 5))
+
+/**
+ * @callback Cb
+ * @param {V} firstParam
+ */
+/**
+ * @template V
+ * @param {V} vvvvv
+ */
+function g(vvvvv) {
+>g : Symbol(g, Decl(github20832.js, 12, 12))
+>vvvvv : Symbol(vvvvv, Decl(github20832.js, 22, 11))
+}
+
+/** @type {Cb} */
+const cb = x => {}
+>cb : Symbol(cb, Decl(github20832.js, 26, 5))
+>x : Symbol(x, Decl(github20832.js, 26, 10))
+
diff --git a/tests/baselines/reference/typedefTagTypeResolution.types b/tests/baselines/reference/typedefTagTypeResolution.types
new file mode 100644
index 0000000000000..20c9412832667
--- /dev/null
+++ b/tests/baselines/reference/typedefTagTypeResolution.types
@@ -0,0 +1,40 @@
+=== tests/cases/conformance/jsdoc/github20832.js ===
+// #20832
+/** @typedef {U} T - should be "error, can't find type named 'U' */
+/**
+ * @template U
+ * @param {U} x
+ * @return {T}
+ */
+function f(x) {
+>f : <U>(x: U) => any
+>x : U
+
+    return x;
+>x : U
+}
+
+/** @type T - should be fine, since T will be any */
+const x = 3;
+>x : any
+>3 : 3
+
+/**
+ * @callback Cb
+ * @param {V} firstParam
+ */
+/**
+ * @template V
+ * @param {V} vvvvv
+ */
+function g(vvvvv) {
+>g : <V>(vvvvv: V) => void
+>vvvvv : V
+}
+
+/** @type {Cb} */
+const cb = x => {}
+>cb : Cb
+>x => {} : (x: any) => void
+>x : any
+
diff --git a/tests/cases/conformance/jsdoc/paramTagTypeResolution.ts b/tests/cases/conformance/jsdoc/paramTagTypeResolution.ts
new file mode 100644
index 0000000000000..0256651234d25
--- /dev/null
+++ b/tests/cases/conformance/jsdoc/paramTagTypeResolution.ts
@@ -0,0 +1,13 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @Filename: first.js
+/** @template T
+ * @param {T} x
+ * @param {(t: T) => void} k
+ */
+module.exports = function (x, k) { return k(x) }
+
+// @Filename: main.js
+var f = require('./first');
+f(1, n => { })
diff --git a/tests/cases/conformance/jsdoc/typedefTagTypeResolution.ts b/tests/cases/conformance/jsdoc/typedefTagTypeResolution.ts
new file mode 100644
index 0000000000000..c4c993d9c78e0
--- /dev/null
+++ b/tests/cases/conformance/jsdoc/typedefTagTypeResolution.ts
@@ -0,0 +1,32 @@
+// @noEmit: true
+// @allowJs: true
+// @checkJs: true
+// @Filename: github20832.js
+
+// #20832
+/** @typedef {U} T - should be "error, can't find type named 'U' */
+/**
+ * @template U
+ * @param {U} x
+ * @return {T}
+ */
+function f(x) {
+    return x;
+}
+
+/** @type T - should be fine, since T will be any */
+const x = 3;
+
+/**
+ * @callback Cb
+ * @param {V} firstParam
+ */
+/**
+ * @template V
+ * @param {V} vvvvv
+ */
+function g(vvvvv) {
+}
+
+/** @type {Cb} */
+const cb = x => {}