The invention provides a method for determining the rigidity and the bearing capacity of a shear connector. The method comprises the steps that a connecting piece web of a bulkhead type double-steel-plate-concrete combined structure serves as a foundation beam, concrete serves as a foundation, an elastic foundation beam model is established, and a general solution of a differential equation of theelastic foundation beam model is obtained through calculation according to the elastic foundation beam model; the shear connector is analyzed according to a model corresponding to the bulkhead type double steel plate-concrete composite structure, a boundary condition is determined, and a rigidity parameter of the shear connector is calculated and obtained according to the boundary condition and the shear-deformation relationship; and based on the elastic foundation beam theory, the ultimate bearing capacity of the shear connector is obtained through calculation according to the plasticity development coefficient. By applying the method, the rigidity and the bearing capacity of the shear connector can be accurately predicted.