In order to ensure the work reliability of electromechanical equipment,it is necessary to maintain the equipment in time.Study on reliability and maintenance cost of electromechanical equipment is great significance to improve the efficiency and to reduce the production total cost of equipment.The system reliability model and maintenance cost model of electromechanical equipment were established based on the failure probability density function of parts.Taking the normal distribution for example,the influence caused by the parameters of parts failure probability density function,maintenance cycle on the system reliability and maintenance cost were analyzed by simulation.