Abstract: A pressure line card of H62 brass in the electric connector was found to have fractured after storage for six months. In the present work, the failure mode and cause of the pressure line card were analyzed by micro and macro observation, EDS analysis, hardness test and metallurgical structure examination. And the artificial fracture surface, hardness, metallurgical structure of a good pressure line card of the same batch were analyzed for comparison with the failed one. The results show the failure mode is stress corrosion. There were two causes for the failure that one was high tensile stress led by the high volume of heat crinkle membrane in the pressure line card; another was that the damage of the surface plating resulted in the loss of its protection function. The volume of the heat crinkle membrane should be controlled, and the surface plating should be protected during production, storage and service.