Abstract: Fault tree analysis on existing models can not solve complex environment of multiple uncertainties，the use of the random fuzzy variables primitive opportunity to propose a random fuzzy fault tree top incident primitive opportunities algorithm.The basic idea of this algorithm is to first go through fuzzy simulation to produce a group of fuzzy numbers which satisfied with the requirement，and then use these fuzzy numbers as parameters carry through random simulation to achieve the primitive opportunity of top event.Finally，examples show that the algorithm in solving the problem of double fuzzy uncertainty than any fault tree algorithm has advantages.

摘要： 针对现有故障树分析模型无法解决复杂环境下的多重不确定性问题，利用随机模糊变量的本原机会概念，提出了随机模糊故障树顶事件本原机会的求解算法。该算法的基本思想是先通过模糊模拟产生一组符合要求的模糊数，然后利用这些模糊数做参数进行随机模拟求得顶事件的本原机会。最后，通过实例证明了该算法在解决双重不确定方面比任何模糊故障树算法都有优势。