For the problem that the finite element simulation analysis of temperature field of large rubber coupling of ships is difficult to convergence because of the large load,the large deformation of rubber piece parts and the nonlinear characteristics of rubber materials,by using the decoupling method,combined with the node equivalence method,the finite element mathematical mode of the rubber material thermal analysis is established theoretically. With some kind of diaphragm rubber couplings as an example,the thermal of its rubber element is analyzed,the steady temperature distribution and transient temperature field curve are got. Studying of the results by using least square method,finds that the relationship of the maximum temperature rise with load torque is a parabola,and the relationship of the maximum temperature rise with load with load frequency is a linear. The simulation results and the experimental results that obtained through torsion test have a good consistency. The feasibility of this approach is proved,and it has the guiding significance for the actual work.