Abstract: In view of the lack of specific application of energy efficiency indicators of PV power station,the boundary of PV module power generation efficiency is fuzzy,and the I-V characteristic curve of PV modules during normal operation of PV power station is difficult to obtain,which makes the current method of identifying abnormal PV modules difficult to apply to actual PV power station. Based on this,this paper proposes a identification of abnormal PV module energy efficiency in PV power stations based on t-test method,utilizing the characteristic that the performance ratio of PV modules follows a normal distribution. Hypothesis testing is conducted on the difference between the actual and theoretical performance ratios of PV modules,and combined with actual PV power station for experimental verification. The research results show that this method can effectively identify abnormal PV modules and provide data support for the operation and maintenance of PV power stations.