Considering the complicated relation of triangle labyrinth channel parameters to hydraulic performance, the explicit analytical model was not figured out. Moving least squares response surface methodology was introduced to build parameter sensitivity model corresponding to reliability of hydraulic performance. The analysis of parameter sensitivity shows that the length and the width of triangle labyrinth channel parameters have great influence on the reliability of flux coefficient. Meanwhile, the width, and the angle of triangle labyrinth channel parameters have great influence on the reliability of flow index. Standard deviation increasing in the parameters of triangle labyrinth channel will reduce the reliability of flux coefficient and flow index. The reliability sensitivity analysis for hydraulic performance demonstrates that the result of presented method is accord with the qualitative analysis. Thus the proposed method is efficient and accurate.