Water strider is an insect that can walk on water surface and will not sink using the especial structure of its legs. Based on the basic principle that water strider can walk on water surface, a novel bionic Miniature Water Strider Robot that can walk on water surface is put forward in this paper. The 3D model of the Miniature Water Strider Robot is established in the Pro/E. Based on this, the finite element model is set up using ANSYS software and the modality analysis of the robot is carried out. The five natural frequency and vibration mode are solved. The unsubstantial areas and resonant areas of the robot structure can be found through the modality analysis on the structure of the miniature water strider robot, and the credible data to modify the structure dynamic design can be offered.