Abstract: Based on new potential and complementary energy densities of coupled thermo-elasticity, we have established a series of generalized principles of action for coupled thermo-elasticity, making use of Lagrange multiplier method and the match relation.between the variational conditions, the variational constraint conditions and the general constraint conditions. These generalized principles of action lay the foundation theoretically for approximate and numerical methods of solving the problems of coupled thermo-elastieity theory.