Asymmetric lifting and dismantling platform is selected as the research object. The main characteristics of the research object different from the traditional platform are the asymmetric main hull structure without transverse brace and the great arc structure at the connection between the vertical column and the upper deck. In order to verify the performance of the air gap response of this new platform, ANSYS Waorkbench is used to establish a three-dimensional finite element model of the platform and STAR CCM+ software is used to conduct hydrodynamic analysis on the research object and the traditional platform to study the influence of two different forms on the air gap and wave slamming response, and to study the characteristics of the large angle connection structure through numerical simulation. The results show that: due to the asymmetric characteristics of the column of the target platform, the air gap is located on the side of the hull, and the wave slamming response is different from that of the traditional semi-submersible platform; the structural strength of the connection between the column and the lower deck is effectively improved by the large angle connection structure. According to the simulation test results, the key areas prone to wave nonlinear phenomena such as wave slamming can be strengthened purposefully, so as to ensure the safety of the platform under harsh working conditions and provide certain reference for the design of the relevant platforms.