The Maintenance system is an important factor that can boost the productivity of a company, likewise for PT XYZ which is engaged in the jig and tool industry. In fulfilling the customer demand, work productivity is needed in company, especially in the company’s machine maintenance system. There are many machine problems that occur at PT XYZ, such as downtime due to the company’s production machines. This can cause the production process to stop suddenly and can even cause losses due to maintenance that occurs due to the damage. The research was carried out on the CNC milling tape drill machine which has the most downtime frequency of 70 times with a time reaching 206.15 working hours during 2017 to 2019. This study provides maintenance proposal at PT XYZ by implementing preventive maintenance with age replacement method which then obtained a cost comparison between the maintenance model used by PT XYZ now and the proposal. From the Research results, there are 4 critical components because they have a Risk Priority Number value that is above the critical of RPN, where the four components are the solenoid valve with an RPN value of 180, a plarail chain of 150, a spindle motor of 140, and signal lamp of 180 where the critical value of RPN is 123.54. From this study also obtained the optimal replacement time interval for 4 critical components where the optimal replacement is on the 41st day for solenoid valve, 38th day for plarail chain, 207th day for motor spindle, and 90th day for signal lamp. Then obtained the difference in maintenance costs is IDR 39.356.404 if PT XYZ implements preventive maintenance using the age replacement method.