diff --git a/src/core/render/compiler.js b/src/core/render/compiler.js
index 557507721..6d183102f 100644
--- a/src/core/render/compiler.js
+++ b/src/core/render/compiler.js
@@ -63,6 +63,7 @@ export class Compiler {
     this.router = router;
     this.cacheTree = {};
     this.toc = [];
+    this.uniqueTOC = [];
     this.cacheTOC = {};
     this.linkTarget = config.externalLinkTarget || '_blank';
     this.linkRel =
@@ -235,7 +236,12 @@ export class Compiler {
       const slug = slugify(config.id || str);
       const url = router.toURL(router.getCurrentPath(), { id: slug });
       nextToc.slug = url;
-      _self.toc.push(nextToc);
+
+      // FIXME: Maybe we can do the de-duplication directly from _self.toc
+      if (_self.uniqueTOC.indexOf(url) === -1) {
+        _self.uniqueTOC.push(url);
+        _self.toc.push(nextToc);
+      }
 
       return `<h${level} id="${slug}"><a href="${url}" data-id="${slug}" class="anchor"><span>${str}</span></a></h${level}>`;
     };