Abstract: In the containment hydrogen analysis, there is uncertainty in the computation results because uncertainty exists in the input parameters. It is of great importance for the safety issue to study the variation ranges of the computation results as well as the contribution of each input parameter to the uncertainty of the results. In order to numerically simulate the hydrogen recombiner case in the containment, the recombiner model is firstly added to the computational fluid dynamics code HYDRAGON. Deflagration-detonation-transformation index, total explosion energy and related instance variables, are selected as objects of the study. Numerical simulations are performed after sampling for certain input parameters. The uncertainty of the computational results is studied with nonparametric statistical method and the variation ranges of the results are provided. Furthermore, the sensitivity between the computational results and the input parameters are investigated. The input parameters, whose uncertainty has larger influence on the computational results, are also screened out.