In hydraulic engineering, sluice is widely used as a water retaining and overflowing structure. The interaction between the sluice chamber and foundation is complex and intense especially for the chambers built on soil foundations. The floor of the sluice chamber is the connecting member between the chamber and the foundation, its working behavior has a great impact on the performance and safe operation of the sluice. In this paper, the foundation reaction force was taken as the characterization index of the interaction between the chamber and the foundation. The influence factors of the foundation reaction force and their effects were studied based on the active design code, the Markov chain Monte Carlo (MCMC) sampling method, the back propagation (BP) neural network and the Tchaban sensitivity analysis method. The proposed method was then applied to a practical engineering analysis. The research results have important theoretical value for in-depth understanding and studying of the foundation reaction to the sluice chamber floor and the interaction mechanism between the sluice chamber structure and the foundation. Also the results can provide some reference for the rational design, safe operation and scientific evaluation of sluice works.