Taking the Qingju ship lock project in Sichuan province as the background, this paper calculates the inner force of lock chamber structure by Plane Simplified Method and Finite Element Method, and carries out an analysis on the prototype observation data, which shows that the Plane Simplified Method is difficult to meet the need of calculation for asymmetric gate double wall floor type reaming of ship lock structures, while the calculation results based on the nonlinear finite element method tallies better with the real stress state. Moreover, it can reflect the most unfavorable position of internal ship lock structures, stress state and the changing laws, and the results may serve as reference for the engineering design of the ship lock.