Abstract: FCM (Fuzzy Cognitive Map), as an intelligent computational tool, can indicate the relationships among multiple factors in direct or indirect through knowledge expression, reasoning and calculation. Considering the characteristics of client services in the video grid with hybrid architecture, FCM was introduced to calculate the service ability of clients, in which, the client network bandwidth, the film hot degree, the number of on-line users, the user on-line duration were taken as the influence factors. The results show that the method for calculating the client service ability based on FCM has the features of high-accuracy, quick calculation speed, good stability in video grid with hybrid architecture, and it can be used in real application systems.