The embodiment of the invention provides a data transmission device and method. The device comprises a security module and a server module which are in communication connection, the server module is used for receiving a request from external equipment, determining a communication protocol for communicating with the security module based on the type of the request, and forwarding the request to thesecurity module based on the communication protocol; and the security module is used for correspondingly processing the request according to the communication protocol and returning a processing result to the external equipment through the server module.