diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7f2b9ca..06c7913 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# Unreleased
+
+### Misc
+
+- Added guard against undefined `HTMLElement` in `callSubscriber` for SSR
+
 # [7.0.0](https://github.com/ZeeCoder/use-resize-observer/compare/v6.1.0...v7.0.0) (2020-11-11)
 
 ### Bug Fixes
diff --git a/src/index.ts b/src/index.ts
index e5a365a..7f37779 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -38,7 +38,7 @@ function useResolvedElement<T extends HTMLElement>(
       element = callbackRefElement.current;
     } else if (refElement.current) {
       element = refElement.current;
-    } else if (refOrElement instanceof HTMLElement) {
+    } else if (typeof HTMLElement !== "undefined" && refOrElement instanceof HTMLElement) {
       element = refOrElement;
     }
 
@@ -59,7 +59,7 @@ function useResolvedElement<T extends HTMLElement>(
     }
   };
 
-  if (refOrElement && !(refOrElement instanceof HTMLElement)) {
+  if (refOrElement && typeof HTMLElement !== "undefined" && !(refOrElement instanceof HTMLElement)) {
     // Overriding the default ref with the given one
     ref = refOrElement;
   }