In order to develop the structural components of the space telescope star coronagraph, the mode of the module structural components of the star coronagraph was studied. A simplified design method of the module structural components of the star coronagraph based on modal analysis was proposed. The structure of the space star coronagraph of the survey optical telescope of the space station is studied. The first order mode of the formal scheme is 115.85 Hz, and the first order mode of the simplified design structure is 133.1 Hz. The simplified design meets the requirements. The natural frequency, mode and modal damping ratio of the first order mode are obtained by modal test. The first mode of the test is 129 Hz, which meets the design requirements of >100 Hz, and the structural stiffness of the product is good. The relative error of modal simulation and test is 3.2%, which can be used as dynamic model for finite element analysis of vibration and shock response spectrum. At the same time, it provides ideas for the design of other load structural parts.