In order to carry out the probability fragility analysis(PSA), the probability fragility evaluation of a electrical cabinet qualified by testing was conducted based on the relationship between anti-seismic capacity of the component and the conditional failure probability, and also the lognormal characteristics of the fragility model. As a result, the median value of capacity(0.75g), logarithmic standard deviation of random(0.21), logarithmic standard deviation of uncertainty(0.50) and high confidence and low probability failure(HCLPF) value(0.23g) were obtained. The analysis method presented in this paper provides reference for successive seismic probability fragility analysis of electric equipment.