The present invention discloses an authority control method and system of a video monitoring system. A plurality of roles and authorities rated to each role are arranged; and thus, if the authority related to some role conforms with an user, after the role is distributed to the user, the authority related to the gained role can be directly given to the user, and each authority conforming with the user does not need to be related to the users one by one, and then, to be given to the users one by one, so the efficiency of authority arrangement and authority giving in authority control is improved. However, for more users distributed with the same role, if all the authorities conforming with the users need to be corrected, only the authorities related to the roles need to be corrected, while the authority related to each user do not need to be corrected one by one, and thus, the efficiency of authority maintenance in the authority control is simplified.