The water system of coal shearer machine consists of three main subsystems namely spray jets, water & hoses, and filters which are connected and working in series configuration. In this paper the Kamat-Riley Monte Carlo simulation method was used for reliability analysis of the considered system. The studied data was collected from an Iranian longwall coal mine for analysis. The MATLAB software was used for simulation and then reliability plot of water system in shearer machine was determined. The results show that the reliability of shearer machine reduces to almost zero in a period of 300h. Comparison between the results of analytical method and simulated reliability plot presents that for analyzed data set, in high reliability levels (28%≤), the simulation approach estimates the higher reliability than analytical method. The maximum difference between the results of analytical and simulation methods is 23%. However, in low reliability levels (≤28%) there is no remarkable difference between the methods.