Abstract: Using the traditional 2D interpolation-based method to compute hydrostatic performance of ship will result in an unfavorable accuracy and troublesome operation.A new method based on the 3D solid model was proposed,which was constructed in the CATIA environment,and combined to apply VB.NET to develop computing procedures of ship hydrostatic for secondary development.The information required for hydrostatic computation was then auto matically extracted from the solid model.The good operability and reliability was proved by an example of tanker calculation.