Previously, one of the authors developed the new mechanism of plastic hinge based on the plastic flow theory, derived the plastic stiffness matrices of elements and established the plastic hinge method for elastic-plastic analysis of space frame structures accompanied by large deflection. In this paper, the previous theory is further extended for analysis of plastic strength of plates based on the finite element method and a general theory is proposed. Applying this generalized plastic hinge method, several examples including elastic-plastic large deflection problems are analysed, and the effectiveness of this method is demonstrated.