diff --git a/README.md b/README.md
index 3a7249d..00e3be3 100644
--- a/README.md
+++ b/README.md
@@ -152,11 +152,13 @@ easyMDE.value('New input for **EasyMDE**');
 - **uploadImage**: If set to `true`, enables the image upload functionality, which can be triggered by drag&drop, copy-paste and through the browse-file window (opened when the user click on the *upload-image* icon). Defaults to `false`.
 - **imageMaxSize**: Maximum image size in bytes, checked before upload (note: never trust client, always check image size at server-side). Defaults to `1024*1024*2` (2Mb).
 - **imageAccept**: A comma-separated list of mime-types used to check image type before upload (note: never trust client, always check file types at server-side). Defaults to `image/png, image/jpeg`.
+- **imageUploadFunction**: A custom function for handling the image upload. Using this function will render the options `imageMaxSize`, `imageAccept`, `imageUploadEndpoint` and `imageCSRFToken` ineffective.
+    - The function gets a file and onSuccess and onError callback functions as parameters. `onSuccess(imageUrl: string)` and `onError(errorMessage: string)`
 - **imageUploadEndpoint**: The endpoint where the images data will be sent, via an asynchronous *POST* request. The server is supposed to save this image, and return a json response.
      - if the request was successfully processed (HTTP 200-OK): `{"data": {"filePath": "<filePath>"}}` where *filePath* is the relative path of the image;
      - otherwise: `{"error": "<errorCode>"}`, where *errorCode* can be `noFileGiven` (HTTP 400), `typeNotAllowed` (HTTP 415), `fileTooLarge` (HTTP 413) or `importError` (see *errorMessages* below). If *errorCode* is not one of the *errorMessages*, it is alerted unchanged to the user. This allows for server side error messages.
      No default value.
-- **imageCSRFToken**: CSRF token to include with AJAX call to upload image. For instance used with Django backend. 
+- **imageCSRFToken**: CSRF token to include with AJAX call to upload image. For instance used with Django backend.
 - **imageTexts**: Texts displayed to the user (mainly on the status bar) for the import image feature, where `#image_name#`, `#image_size#` and `#image_max_size#` will replaced by their respective values, that can be used for customization or internationalization:
     - **sbInit**: Status message displayed initially if `uploadImage` is set to `true`. Defaults to `Attach files by drag and dropping or pasting from clipboard.`.
     - **sbOnDragEnter**: Status message displayed when the user drags a file to the text area. Defaults to `Drop image to upload it.`.
diff --git a/src/js/easymde.js b/src/js/easymde.js
index 8beb664..5e2376c 100644
--- a/src/js/easymde.js
+++ b/src/js/easymde.js
@@ -1640,11 +1640,19 @@ function EasyMDE(options) {
         this.codemirror.on('drop', function (cm, event) {
             event.stopPropagation();
             event.preventDefault();
-            self.uploadImages(event.dataTransfer.files);
+            if (options.imageUploadFunction) {
+                self.uploadImagesUsingCustomFunction(options.imageUploadFunction, event.dataTransfer.files);
+            } else {
+                self.uploadImages(event.dataTransfer.files);
+            }
         });
 
         this.codemirror.on('paste', function (cm, event) {
-            self.uploadImages(event.clipboardData.files);
+            if (options.imageUploadFunction) {
+                self.uploadImagesUsingCustomFunction(options.imageUploadFunction, event.clipboardData.files);
+            } else {
+                self.uploadImages(event.clipboardData.files);
+            }
         });
     }
 }
@@ -1669,6 +1677,25 @@ EasyMDE.prototype.uploadImages = function (files, onSuccess, onError) {
     this.updateStatusBar('upload-image', this.options.imageTexts.sbOnDrop.replace('#images_names#', names.join(', ')));
 };
 
+/**
+ * Upload asynchronously a list of images to a server.
+ *
+ * Can be triggered by:
+ * - drag&drop;
+ * - copy-paste;
+ * - the browse-file window (opened when the user clicks on the *upload-image* icon).
+ * @param imageUploadFunction {Function} The custom function to upload the image passed in options.
+ * @param {FileList} files The files to upload the the server.
+ */
+EasyMDE.prototype.uploadImagesUsingCustomFunction = function (imageUploadFunction, files) {
+    var names = [];
+    for (var i = 0; i < files.length; i++) {
+        names.push(files[i].name);
+        this.uploadImageUsingCustomFunction(imageUploadFunction, files[i]);
+    }
+    this.updateStatusBar('upload-image', this.options.imageTexts.sbOnDrop.replace('#images_names#', names.join(', ')));
+};
+
 /**
  * Update an item in the status bar.
  * @param itemName {string} The name of the item to update (ie. 'upload-image', 'autosave', etc.).
@@ -2058,6 +2085,42 @@ EasyMDE.prototype.uploadImage = function (file, onSuccess, onError) {
 
 };
 
+/**
+ * Upload an image to the server using a custom upload function.
+ *
+ * @param imageUploadFunction {Function} The custom function to upload the image passed in options
+ * @param file {File} The image to upload, as a HTML5 File object (https://developer.mozilla.org/en-US/docs/Web/API/File).
+ */
+EasyMDE.prototype.uploadImageUsingCustomFunction = function(imageUploadFunction, file) {
+    var self = this;
+    function onSuccess(imageUrl) {
+        afterImageUploaded(self, imageUrl);
+    }
+
+    function onError(errorMessage) {
+        var filledErrorMessage = fillErrorMessage(errorMessage);
+        // show error on status bar and reset after 10000ms
+        self.updateStatusBar('upload-image', filledErrorMessage);
+
+        setTimeout(function () {
+            self.updateStatusBar('upload-image', self.options.imageTexts.sbInit);
+        }, 10000);
+
+        // run error handler from options, this alerts the message.
+        self.options.errorCallback(filledErrorMessage);
+    }
+
+    function fillErrorMessage(errorMessage) {
+        var units = self.options.imageTexts.sizeUnits.split(',');
+        return errorMessage
+            .replace('#image_name#', file.name)
+            .replace('#image_size#', humanFileSize(file.size, units))
+            .replace('#image_max_size#', humanFileSize(self.options.imageMaxSize, units));
+    }
+
+    imageUploadFunction(file, onSuccess, onError);
+};
+
 EasyMDE.prototype.createSideBySide = function () {
     var cm = this.codemirror;
     var wrapper = cm.getWrapperElement();
diff --git a/types/easymde-test.ts b/types/easymde-test.ts
index 12b0555..103569b 100644
--- a/types/easymde-test.ts
+++ b/types/easymde-test.ts
@@ -1,4 +1,6 @@
 // Create new instance
+import EasyMDE = require('./easymde');
+
 const editor = new EasyMDE({
     autoDownloadFontAwesome: false,
     element: document.getElementById('mdEditor')!,
@@ -40,7 +42,7 @@ const editor2 = new EasyMDE({
         title: 'Bold',
     }, '|', { // Separator
         name: 'alert',
-        action: (editor) => {
+        action: (editor: EasyMDE) => {
             alert('This is from a custom button action!');
             // Custom functions have access to the `editor` instance.
         },
@@ -84,3 +86,30 @@ const editorImages = new EasyMDE({
         console.error(errorMessage);
     },
 });
+
+const editorImagesCustom = new EasyMDE({
+    uploadImage: true,
+    imageAccept: 'image/png, image/bmp',
+    imageCSRFToken: undefined,
+    imageMaxSize: 10485760,
+    imageUploadFunction: (file: File, onSuccess: Function, onError: Function) => {
+        console.log(file)
+    },
+    imageTexts: {
+        sbInit: 'Drag & drop images!',
+        sbOnDragEnter: 'Let it go, let it go',
+        sbOnDrop: 'Uploading...',
+        sbProgress: 'Uploading... (#progress#)',
+        sbOnUploaded: 'Upload complete!',
+        sizeUnits: 'b,Kb,Mb'
+    },
+    errorMessages: {
+        noFileGiven: 'Please select a file',
+        typeNotAllowed: 'This file type is not allowed!',
+        fileTooLarge: 'Image too big',
+        importError: 'Something went oops!',
+    },
+    errorCallback: (errorMessage) => {
+        console.error(errorMessage);
+    },
+  });
diff --git a/types/easymde.d.ts b/types/easymde.d.ts
index 2a7db40..1fa121c 100644
--- a/types/easymde.d.ts
+++ b/types/easymde.d.ts
@@ -134,6 +134,7 @@ declare namespace EasyMDE {
         uploadImage?: boolean;
         imageMaxSize?: number;
         imageAccept?: string;
+        imageUploadFunction?: (file: File, onSuccess: Function, onError: Function) => void;
         imageUploadEndpoint?: string;
         imageCSRFToken?: string;
         imageTexts?: ImageTextsOptions;