The embodiment of the invention discloses a multimedia data processing method and equipment and system thereof. The method comprises the following steps: a first terminal acquires online multimedia data corresponding to a first application identifier from an application server based on an instant messaging application; the first terminal acquires a second application identifier selected for the online multimedia data from a contact list corresponding to the first application identifier; the first terminal sends the second application identifier to the application server; the application serverreceives the second application identifier sent by the first terminal, and sends the online multimedia data to a second terminal corresponding to the second application identifier; and the second terminal receives the online multimedia data sent by the application server, acquires the processing information on the online multimedia data, and synchronizes the processing information to the application server. By adopting the data processing method disclosed by the embodiment of the invention, the sharing of the online multimedia data can be realized by combining the instant messaging application, an operation process of the data sharing is simplified, and the processing efficiency of the multimedia data is guaranteed.