diff --git a/lib/model.js b/lib/model.js
index 4ce3e39e648..84b4220bd3d 100644
--- a/lib/model.js
+++ b/lib/model.js
@@ -3323,7 +3323,7 @@ Model.$__insertMany = function(arr, options, callback) {
         }
 
         // `insertedDocs` is a Mongoose-specific property
-        const erroredIndexes = new Set(error.writeErrors.map(err => err.index));
+        const erroredIndexes = new Set(get(error, 'writeErrors', []).map(err => err.index));
         error.insertedDocs = docAttributes.filter((doc, i) => {
           return !erroredIndexes.has(i);
         });