The invention provides a rigidity changeable plate spring structure. The rigidity changeable plate spring structure comprises an overall length spring piece, one end of the overall length spring piece is upwards bent to be provided with a first spring eye, the other end of the overall length spring piece is upwards bent or downwards bent, and a buffering cushion is arranged at the other end of the overall length spring piece. The middle of the overall length spring piece is a first straight segment, the first straight segment is provided with a center bolt hole, and a half-length spring piece is fixed to the first straight segment through a center bolt and a nut. One end of the half-length spring piece is a second straight segment, and the other end of the half-length spring piece is upwards bent to be provided with a second spring eye. The first straight segment and the second straight segment are fixedly connected through a center bolt and a nut. A gasket is arranged between the first straight segment of the overall length spring piece and the second straight segment of the half-length spring piece. According to the rigidity changeable plate spring structure, the overall length spring piece and the half-length spring piece are combined together, a main spring and an auxiliary spring are formed, the plate spring structure with a simple structure is formed, the rigidity changing characteristic is achieved, the mass of the plate spring assembly is reduced, and light weight is achieved.