A pump is a machine or mechanical equipment that is used to raise fluid from lowland to highland or to increase fluid pressure from low pressure fluid to high pressure fluid and also as a flow rate amplifier in a transfer network system. In order to ensure that the performance of a pump can operate well and optimally, it is necessary to have a good maintenance system because the smoothness of the production process is influenced by the maintenance applied. Maintenance or what is usually referred to as maintenance is an activity carried out to maintain the condition of a facility (machinery, equipment and a system) in a condition where the system can operate/function properly, which is done by limiting and eliminating damage to the system. In order for the maintenance system to be more scheduled, it is necessary to know the reliability of each critical component in the pump. Reliability is obtained by using the risk based inspection method to determine the cause of damage to critical components. The results obtained from this analysis are six critical components that have MTTF and reliability values, namely at an interval of 600 HM hours, o-ring - AP.850.76 is 56.84% at 1826.57 hours, o-ring - AP.850.80 is 56.84% at 1826.57 hours, out ring – AP.850.43 is 56.84% at 1826.57 hours, wear ring – AP.850.44 is 56.84% at 1826.57 hours, bellmouth – AP.850.42 is 55.02% at 2204.11 hours, bearing – AP.850.20 is 54.88% at 2626.83 hours.