Fatigue fracture and wear of bottom pintle are the primary causes of ship lock gates' maintenance. During the structural design of bottom pintle, nonlinear contact analysis on bottom pintle should be carried out to examine its strength and to propose improvement measures of structure design. Taking the downstream sector gate of ship lock at the Chahe River for an example, the methods of nonlinear contact finite element analysis on bottom pintle by using the software Workbench were introduced in detail in this study. The deformation and contact stress of bottom pintle under the action of front and back hydraulic pressure were comparatively analyzed. The results showed that, the whole structure of bottom pintle met the standard requirements, the contact surfaces of bottom pintle under back hydraulic pressure were more likely to lose efficacy; circular chamfering or rounded corners should be set at local stress concentration areas to avoid great abrupt changes of dimension in structure. This study provides an important reference for structural design of bottom pintle.