Abstarct: One of the necessary requirement for desirable and acceptable performance in mining production system is high availability of equipment in system. Equipment’s failures are one sources of costs in a system. Reliability analysis is subject that study this failures and used for optimizing performance, reducing overall costs and increasing life cycle of equipment and facilities. With this subject we control availability state of machines. Maintenance, repair and operations with emphasis on keeping system reliability in expected level is used to have desired level of availability and safety and decrease productions risks. In this research we considered Siriz 1 (Sadat 5) iron mine production system that include drilling, loading and transportation subsystems. After gathering related data about machines failures, we determined failure density function of machines and reliability of subsystems. We considered machines in parallel for calculating subsystem’s reliability. Reliability of drilling subsystem reach 50% after 50 hours and reach zero after 300 hours. For loading and transportation subsystems, it reach zero after 900 and 1100 hours respectively. Because these subsystems work in series, reliability of system as a whole reach zero after 300 hours and performance of production system can improve as a result of drilling subsystem’s performance improvement. maintainability is calculated to determine ability of a damaged or failed machine or system to be restored to acceptable operating condition. Preventive Maintenance (PM) schedules is proposed to keep reliability of machines in 70%. Reliability of subsystems calculated respect to these schedules. Reliability of transportation subsystem improved to 100% (all the time) as a result of PM and reliability of loading and drilling subsystems and production system as a whole increased to 99%-100%, 93%-100% and 93%-100% respectively