diff --git a/.changeset/witty-dodos-guess.md b/.changeset/witty-dodos-guess.md
new file mode 100644
index 000000000..b9ecf8c5c
--- /dev/null
+++ b/.changeset/witty-dodos-guess.md
@@ -0,0 +1,6 @@
+---
+"myst-transforms": patch
+"myst-cli": patch
+---
+
+Support details/summary in HTML
diff --git a/packages/myst-transforms/src/html.ts b/packages/myst-transforms/src/html.ts
index 39134b284..5eea6b535 100644
--- a/packages/myst-transforms/src/html.ts
+++ b/packages/myst-transforms/src/html.ts
@@ -137,6 +137,13 @@ const defaultHtmlToMdastOptions: Record<keyof HtmlTransformOptions, any> = {
       const attrs = addClassAndIdentifier(node);
       return attrs.label ? h(node, 'cite', attrs, all(h, node)) : all(h, node);
     },
+    details(h: H, node: any) {
+      const attrs = addClassAndIdentifier(node);
+      return h(node, 'details', attrs, all(h, node));
+    },
+    summary(h: H, node: any) {
+      return h(node, 'summary', all(h, node));
+    },
   },
 };