The invention discloses a system disk verifying method and a system disk verifying device. The method comprises the steps of verifying the signature of a system disk verifying table, wherein the signature is an information authentication code generated by using an information authentication code generation algorithm; if the signature verifying is passed, according to the system disk verifying table, further acquiring the Hash tree of a system disk and verifying whether the Hash tree is correct; if the Hash tree is correct, further verifying that whether the Hash tree is generated according to the data of the system disk; and if the result of the further verifying is yes, determining that the verifying of the system disk is passed. A corresponding device is also disclosed. According to the system disk verifying method and device, the information authentication code is used as the signature of the system disk verifying table for verifying, thus less computation is required, and the verifying efficiency of the system disk can be improved.