Method for safely powering off STB (Set Top Box)

The invention provides a method for safely powering off an STB (Set Top Box). The method comprises the following steps of receiving a first power-off command sent by a remote controller by the STB; preserving data information of a user by the STB; judging whether a storage device needs to be connected or not by the STB; switching off a command for operating the storage device by the STB if the STB is connected with the storage device; unloading an external device if the external device exists in the STB; sending a second power-off command to an SCM (Single Chip Microcomputer) by the STB; and safely powering off the STB. Compared with the prior art, the method for safely powering off the STB, provided by the invention, is realized by carrying out communication with the SCM, the safety performance of the STB is increased, data loss caused by direct interruption of power supply cannot be caused, the user information can be safely preserved, or the storage device such as a USB (Universal Serial Bus) flash disk can be safely unloaded.