The invention provides a method and a system of antivirus solution by using a SIM card combined with cloud antivirus. The method comprises that the signature data of a file of a present mobile device is sent to a cloud server; the cloud server receives the file the signature data and checks the received file the signature data by using a cloud virus database stored at the cloud server; and the cloud server sends the checking result back to the SIM card of the mobile device via OTA (Over-the-Air).The invention has the advantage of using the SIM card as the media of antivirus and communication so as to be convenient for the cooperation between a telecommunication service provider and an antivirus software vendor.