The embodiment of the invention relates to the communication technology field, and discloses a data protection method and device. The method comprises: detecting whether a data protection mode triggering event aiming at a registration terminal is received or not; if the data protection mode triggering event aiming at the registration terminal is received, sending a data protection mode starting instruction to the registration terminal, wherein the data protection mode starting instruction is configured to indicate the registration terminal to send backup data and format the registration terminal; and receiving the backup data sent by the registration terminal, and performing backup of the backup data. According to the embodiment of the invention, the data protection method and device can reduce the probability of data leakage.