The invention discloses a wind power converter IGBT module junction temperature online computing method, in particular to a wind power converter IGBT module junction temperature online computing method based on switching period loss analysis. On the premise that an IGBT module electric-heating coupling characteristic is considered, the method utilizes a wind power converter to perform IGBT module junction temperature online computation based on real-time operating parameters in a switching period. On the one hand, loss influence of IGBT module junction temperatures at all of moments can be considered; on the other hand, the influence of IGBT module loss energy and waveforms on junction temperature fluctuation within an output period can be further considered, a dynamic fluctuation junction temperature of an IGBT module can be accurately computed in real time when the output frequency of the wind power converter is low, online integration of IGBT module state monitoring and healthy management is facilitated, and the invalidation risk of the wind power converter is reduced.