The article considers a topical problem of the evaluation and optimization of stocks in the set of spare parts taking into account the direct connection of the set to the model of spare parts kit using the method of statistical modeling. The Monte Carlo method has not been used to design optimal sets of spare parts due to the lack of sufficient literature. It is not still well defined how to apply the Monte Carlo method in this area. The given article provides issues how to apply the Monte Carlo method to solve the given problem.