Due to the upgrading of transmission equipment, specific structural bearing capacity requirements are put forward for transmission towers. The existing transmission tower structures in China need to be reinforced reasonably. The static axial loading tests of leg member are carried out under 24 groups of test conditions for four different connection forms of leg member of transmission tower, which are non-reinforced original section, clamps connection, cross plate connection and one-glyph plate connection. The load-displacement curve, ultimate bearing capacity and load-strain curve of leg members after reinforcement are obtained. By comparing with the bearing capacity of unreinforced members, the effects of connection type, reinforcement location and number of reinforcement points on the reinforcement effect are studied.