The stiffness of jack-up construction platform structure is weak,by offshore large waves and long period of time of swell,the structure produces a violent dynamic response.Based on the linearized equation of Morrison and random wave theory and using ANSYS finite element software,we carry out the modal analysis and transient dynamic response analysis,by which we obtain the frequency characteristics and vibration characteristics.The result provides a theoretical basis for the safety and reliability of evaluation platform,as well as control of the vibration response of the platform structure.