Composite structures have been widely used in the field of aerospace, in order to study the mechanical properties of composites in hygrothermal environments, the pull-through tests of a type of polyimide composite laminates were carried out under three test environments: cold temperature dry(CTD), room temperature dry (RTD) and elevated temperature wet (ETW). The numerical simulation analysis of the RTD test process was carried out. The pull-through strength and failure mode of two typical laminates were obtained by experimental, and the damage evolution process was qualitatively analyzed combined with the simulation results. The results show that the type of polyimide composites have excellent thermal stability. The pull-through strength of the composites under CTD condition is 8.1% ~ 9.0% higher than that under RTD condition, and the pull-through strength of the composites under ETW condition is equivalent to that under RTD condition. Compared with (40/50/10) ply, (30/60/10) ply has higher pull-through strength.