Generally, in the mining industry, reliability modeling and analysis is yet to be recognized as one of the effective and systematic methods for acquiring information about critical units and operations. However, at the LKAB Kiruna Iron Ore Mine in Sweden, which is a world leader in the application of advanced mining technology, reliability and maintainability analysis techniques have been gradually accepted as standard tools for planning and operation of automatic and complex mining systems since the mid-80s. This paper deals with reliability analysis and modeling of the production system at the Kiruna mine. This analysis has helped in identifying the critical and sensitive subsystems in the mine production system which have major failure consequences. Since a large number of random variables (phenomena) are involved in the analysis, a simulation program SIMURES was developed to model the reliability characteristics of the production process and analyze the criticality of the various units and operations. This simulation program has helped in evaluating the gain in production volume with improvement in reliability of the various units and thus forming a basis for future investment for increasing the production system efficiency and capability