The invention provides a communication method and device based on a virtual client identification module. Under a condition that a mobile terminal uses a virtual SIM card, a first message is sent to a server so as to instruct that the mobile terminal is using the virtual SIM card currently and instruct the mobile terminal to interact services with the server by using first encrypted parameters; further the mobile terminal interacts the services with the server by using the received first encrypted parameters; therefore, after the mobile terminal obtains the first parameters, the mobile terminal no longer interacts the services by using the first parameters in a plaintext mode; the security of the first parameters in the virtual SIM card is improved; the mobile terminal can interact the services with the server based on encrypted Ki; and therefore, the security of the Ki is improved.