Upgrade method of STB (set top box)

The invention relates to an upgrade method of an STB in an application program. The upgrade method comprises the following steps: S100, entering into an application menu and detecting whether an upgrade file exists, if the upgrade file exists, entering into S200, or else, exiting the application menu; S200, detecting an upgrade mode of the STB, if the upgrade mode is a file upgrade mode, entering into S300, or else, indicating that the upgrade mode is a partition upgrade mode, and entering into S400; S300, creating an upgrade temporary directory in a root file system, writing in related files, and restarting the STB after success; and S400, rewriting a rootfs partition by using the partition upgrade file, and restarting the STB after successful rewrite. With adoption of the upgrade method of the STB disclosed by the invention, the file upgrade or partition upgrade can be performed according to the characteristics required by upgrade, so that the upgrade program of the STB becomes flexible, and the upgrade time is shortened by using the file upgrade mode on account of less upgrade change; the contents related to upgrade are classified to the partition in the process of great upgrade, so that the upgraded system is more stable.