diff --git a/compiler/src/dotty/tools/repl/ReplCompiler.scala b/compiler/src/dotty/tools/repl/ReplCompiler.scala
index 1bd2323073ae..d80e9871fdee 100644
--- a/compiler/src/dotty/tools/repl/ReplCompiler.scala
+++ b/compiler/src/dotty/tools/repl/ReplCompiler.scala
@@ -88,6 +88,17 @@ class ReplCompiler extends Compiler {
     var valIdx = state.valIndex
     val defs = new mutable.ListBuffer[Tree]
 
+    /** If the user inputs a definition whose name is of the form REPL_RES_PREFIX and a number,
+     *  such as `val res9 = 1`, we bump `valIdx` to avoid name clashes.  lampepfl/dotty#3536 */
+    def maybeBumpValIdx(tree: Tree): Unit = tree match
+      case apply: Apply   => for a <- apply.args  do maybeBumpValIdx(a)
+      case tuple: Tuple   => for t <- tuple.trees do maybeBumpValIdx(t)
+      case patDef: PatDef => for p <- patDef.pats do maybeBumpValIdx(p)
+      case tree: NameTree => tree.name.show.stripPrefix(str.REPL_RES_PREFIX).toIntOption match
+        case Some(n) if n >= valIdx => valIdx = n + 1
+        case _                      =>
+      case _              =>
+
     flattened.foreach {
       case expr @ Assign(id: Ident, _) =>
         // special case simple reassignment (e.g. x = 3)
@@ -101,6 +112,7 @@ class ReplCompiler extends Compiler {
         val vd = ValDef(resName, TypeTree(), expr).withSpan(expr.span)
         defs += vd
       case other =>
+        maybeBumpValIdx(other)
         defs += other
     }
 
diff --git a/compiler/test-resources/repl/i3536 b/compiler/test-resources/repl/i3536
new file mode 100644
index 000000000000..490909db103a
--- /dev/null
+++ b/compiler/test-resources/repl/i3536
@@ -0,0 +1,19 @@
+scala> val res0 = 1
+val res0: Int = 1
+
+scala> res0
+val res1: Int = 1
+
+
+scala> val res99 = 9
+val res99: Int = 9
+
+scala> res99
+val res100: Int = 9
+
+
+scala> val res50 = 5
+val res50: Int = 5
+
+scala> res50
+val res101: Int = 5
diff --git a/compiler/test-resources/repl/i3536_bind b/compiler/test-resources/repl/i3536_bind
new file mode 100644
index 000000000000..96ccdce81356
--- /dev/null
+++ b/compiler/test-resources/repl/i3536_bind
@@ -0,0 +1,4 @@
+scala> val res10 @ Some(_) = Option(1)
+val res10: Some[Int] = Some(1)
+scala> res10
+val res11: Some[Int] = Some(1)
diff --git a/compiler/test-resources/repl/i3536_defdef b/compiler/test-resources/repl/i3536_defdef
new file mode 100644
index 000000000000..04e6045c26c3
--- /dev/null
+++ b/compiler/test-resources/repl/i3536_defdef
@@ -0,0 +1,4 @@
+scala> def res20 = 1
+def res20: Int
+scala> res20
+val res21: Int = 1
diff --git a/compiler/test-resources/repl/i3536_object b/compiler/test-resources/repl/i3536_object
new file mode 100644
index 000000000000..181302939423
--- /dev/null
+++ b/compiler/test-resources/repl/i3536_object
@@ -0,0 +1,4 @@
+scala> object res30 { override def toString = "res30" }
+// defined object res30
+scala> res30
+val res31: res30.type = res30
diff --git a/compiler/test-resources/repl/i3536_patterndef_some b/compiler/test-resources/repl/i3536_patterndef_some
new file mode 100644
index 000000000000..24c8736b57b9
--- /dev/null
+++ b/compiler/test-resources/repl/i3536_patterndef_some
@@ -0,0 +1,5 @@
+scala> val Some((res40, res41)) = Option((1, 0))
+val res40: Int = 1
+val res41: Int = 0
+scala> res40
+val res42: Int = 1
diff --git a/compiler/test-resources/repl/i3536_patterndef_tuple b/compiler/test-resources/repl/i3536_patterndef_tuple
new file mode 100644
index 000000000000..987c28c3a382
--- /dev/null
+++ b/compiler/test-resources/repl/i3536_patterndef_tuple
@@ -0,0 +1,5 @@
+scala> val (res40, res41) = (1, 0)
+val res40: Int = 1
+val res41: Int = 0
+scala> res40
+val res42: Int = 1
diff --git a/compiler/test-resources/repl/i3536_typedef b/compiler/test-resources/repl/i3536_typedef
new file mode 100644
index 000000000000..4db70a4f9c98
--- /dev/null
+++ b/compiler/test-resources/repl/i3536_typedef
@@ -0,0 +1,4 @@
+scala> type res50 = Int
+// defined alias type res50 = Int
+scala> 1
+val res51: Int = 1
diff --git a/compiler/test-resources/repl/i3536_var b/compiler/test-resources/repl/i3536_var
new file mode 100644
index 000000000000..7467ad84c772
--- /dev/null
+++ b/compiler/test-resources/repl/i3536_var
@@ -0,0 +1,4 @@
+scala> var res60 = 1
+var res60: Int = 1
+scala> res60
+val res61: Int = 1