The stability capacity of cold-formed purloins with conventional gauge and span was analyzed under wind uplift. The analysis was divided into two parts. The first part was performed on the stability capacity of C-and Z-shaped simply supported purloins, while the other was performed on the stability capacity of Z-shaped continuous purloins with lapped connections, which was affected by the length of lapped connection, number of spans and so on. The comparison indicates that the formula of specification is considered to be conservative between the results of finite element method and the results of design formula in technical specification for steel structure of light-weight buildings with gabled frames（CECS 102:2002）. According to the above analysis, applicable design formula and methods for simply supported purloins and continuous purloins with lapped connections under wind uplift were proposed.