Wide area monitoring system（WAMS） is applicable to monitor the dynamic behaviors of large interconnected power systems. As grid destabilization occurs only incidentally， there is usually no sufficient and combined test on WAMS， which may lead to potential risks of outage. Hence there is a need to investigate more efficient WAMS test skills. The elementary technical characteristics of WAMS are described. Considering system functions， algorithms and data flow characteristics of WAMS and combining engineering practice， a general test scheme is described.The assessment index on test results is also discussed and the rationality of this scheme is revealed with two case studies.