MongoDB Documentation, Release 3.0.4 item: "ABC2", details: { model: "14Q3", manufacturer: "M1 Corporation" }, stock: [ { size: "M", qty: 50 } ], category: "clothing" }, { item: "MNO2", details: { model: "14Q3", manufacturer: "ABC Company" }, stock: [ { size: "S", qty: 5 }, { size: "M", qty: 5 }, { size: "L", qty: 1 } ], category: "clothing" }, { item: "IJK2", details: { model: "14Q2", manufacturer: "M5 Corporation" }, stock: [ { size: "S", qty: 5 }, { size: "L", qty: 1 } ], category: "houseware" } ]; BulkWriteResult({ "writeErrors" : [ ], "writeConcernErrors" : [ ], "nInserted" : 3, "nUpserted" : 0, "nMatched" : 0, "nModified" : 0, "nRemoved" : 0, "upserted" : [ ] }) Pass the mydocuments array to the db.collection.insert() to perform a bulk insert. db.inventory.insert( mydocuments ); The method returns a BulkWriteResult object with the status of the operation. A successful insert of the docu- ments returns the following object: The nInserted field specifies the number of documents inserted. If the operation encounters an error, the BulkWriteResult object will contain information regarding the error. The inserted documents will each have an _id field added by MongoDB. New in version 2.6. MongoDB provides a Bulk() API that you can use to perform multiple write operations in bulk. The following sequence of operations describes how you would use the Bulk() API to insert a group of documents into a MongoDB collection. Initialize a Bulk operations builder for the collection inventory . Insert Multiple Documents with Bulk Step 1: Initialize a Bulk operations builder. Chapter 3. MongoDB CRUD Operations 94 Step 2: Insert the documents.