The invention relates to a reliability analysis method for an electromechanical actuator based on a fuzzy dynamic fault tree. According to the method, top, intermediate and bottom events of the electromechanical actuator analyzed and determined to establish the dynamic fault tree, a dynamic logic gate is replaced with an algebraic operator, an algebraic model of the dynamic fault tree is converted into and solved, data of a triangular fuzzy set is used to represent the fuzzy reliability of the bottom event, the algebraic model is decomposed into a static subtree and a dynamic subtree for solution, the fuzzy probability of failure of an electromechanical actuator system is obtained via integration, and a weak link of the electromechanical actuator system is determined by analyzing the fuzzy importance degree. The method of the invention can be used to analyze the reliability of the electromechanical actuator effectively, solve the problem that traditional dynamic fault tree analysis is high in the computational complexity, and provides reference for fault positioning of the electromechanical actuator.