diff --git a/src/deserialize.ts b/src/deserialize.ts
index 56df5d8..1b359b3 100644
--- a/src/deserialize.ts
+++ b/src/deserialize.ts
@@ -123,7 +123,7 @@ export default function deserialize(node: MdastNode, opts?: OptionType) {
         type: types.image,
         children: [{ text: '' }],
         [imageSourceKey]: node.url,
-        [imageCaptionKey]: node.alt,
+        [imageCaptionKey]: [{ text: node.alt }],
       };
     case 'blockquote':
       return { type: types.block_quote, children };
diff --git a/test/deserialize/__snapshots__/image.test.ts.snap b/test/deserialize/__snapshots__/image.test.ts.snap
index 27af2ac..35b66cf 100644
--- a/test/deserialize/__snapshots__/image.test.ts.snap
+++ b/test/deserialize/__snapshots__/image.test.ts.snap
@@ -2,7 +2,11 @@
 
 exports[`deserialize image 1`] = `
 Object {
-  "caption": "'Jack's profile picture'",
+  "caption": Array [
+    Object {
+      "text": "'Jack's profile picture'",
+    },
+  ],
   "children": Array [
     Object {
       "text": "",