The hydraulic floating ship lift is a new type vertical ship lift using water as the ascending power and safety measures,which is put forward with independent intellectual property rights in China.In view of the complex structural characteristics of the ship lift,we consider the simple structure from the single tube to start a little bit of complex geometry of the research ideas.We establish the user model by the additional mass method,and develop the Python code to simulate the 6th order mode and the frequency and eigenvector participation coefficients in different depths of the shaft.We analyze the modal characteristics of the superficial depth of the first 6 steels,which is useful for further research.