Reliability is one of the important features of products, systems and parts. Nowadays, as the systems become more complex, the concept of reliability and its optimization has been researched and examined in many research and industrial communities. The application of this concept can be seen in many industrial, communication, satellite systems, etc. In the early stages of system design, many system features such as reliability, weight, cost, and etc are associated with uncertainty due to various reasons such as lifespan, operational conditions, etc. Since the use of the probabilistic approach in solving reliability problems has limitations and can only be used in quantitative analysis of information and in many cases does not produce useful and sufficient results for experts, therefore the use of the approach Fuzzy is much more efficient for solving reliability optimization problems. One of the ways to optimize the reliability is to allocate redundancy. When using redundant components in a subsystem, how the redundant components are used is particular importance. In reliability-redundancy allocation problems, the reliability of components is not known in advance and is considered as a decision variable. In this research, the failure rate of components is considered as Triangular Fuzzy Numbers and the reliability of each system with two active and cold-standby strategies has been calculated using genetic algorithm in two model problems and an industrial system in MATLAB software. In the implementation of the genetic algorithm, the random, tournament and roulette wheel methods have been used to select parents and different types of mutation and crossover operators have been used to produce children. The results have been analyzed and investigated in various series, complex and series-parallel systems and are much more efficient than the results obtained from solving the deterministic model.