In this paper, rigidflexiblethermal coupling dynamic formulation for hub rectangular plate multibody system with large deformation under thermal load is investigated. Based on Kirchhoff assumption, and the nonlinear relationships among the Green strain, the curvature and the absolute coordinates, the nonlinear elastic force is derived. Additionally, the finite element discretized dynamic variational equations of the rectangular plate are derived using absolute nodal coordinate formulation. In order to investigate the rigidflexiblethermal coupling effect, the relationship between the heat flux and the absolute coordinates is also obtained. And through the constrained equations of the multibody system, the rigidflexiblethermal coupling equations are derived, which include the heat conduction equations and the Lagrange dynamic equations of the first kind. Moreover, in order to improve the simulation efficiency, modified central difference method and generalizeda method are combined to solve the heat conduction equations and the dynamic equations. And the discretized equations are solved by using NewtonRaphson method. Satellite and plate multibody system applied with solar heat flux is taken as examples to verify the effectiveness of the formulation. Comparison of the results obtained by noncoupling method and rigidflexiblethermal coupling method shows that the effect of the rigid body motion on the temperature gradient in the thickness direction and thermally induced deformation is significant, which should be taken into account. Furthermore, due to the inclusion of the geometric nonlinear terms, the influence of the axial deformation caused by the temperature increase on the transverse deformation is also taken into consideration.