A major problem of enterprises belonging to the mining sector is the ineffective use of mining machines. In order to improve this situation, it is necessary to take measures aimed at increasing the availability and utilization of machines and improve product quality, and also to keep them in good condition as long as possible. The article presents the results of the effectiveness analysis of using four mining machines, which are part of a mechanized longwall system. Its task is the direct exploitation and transport of minerals from the front zone. The examined set of machines consisted of the longwall shearer, the armoured face conveyor, the beam stage loader and the crusher. For each of the tested machines, the partial effectiveness indicators and the overall effectiveness value based on the Overall Equipment Effectiveness model (OEE) were designated. According to this model, the efficiency ratio is the product of three partial indicators including the availability and the performance of the machine and the product quality. In the present case, the values of all the indicators for the set of machines, which from the reliability point of view create a serial line, were determined. It should be emphasized that the OEE indicator is one of the most important tools used for quantitative evaluation of the Total Productive Maintenance (TPM) strategy. The aim of the strategy is to improve effectiveness through the application of organizational and management techniques that contribute to increased reliability, availability and performance of machines in all stages of production. TPM assumes avoiding, eliminating, predicting and preventing of losses, failures, downtime, defects and other negative events. In addition, according to the strategy it is crucial to build the proper employee attitudes of responsibility for their work and participation in building the success of the entire enterprise. These activities should be more widely used in the coal industry, which is confronted with major economic and social problems. Based on the achieved results it can be claimed that all the analyzed machines showed large overall effectiveness reserves. The value of the OEE indicator for a set of machines in the analyzed period was only 51.9%. The use of machines has proved to be unsatisfactory, especially compared with global OEE standards. Therefore, it is reasonable to utilize wider implementation of the TPM strategy in the mining industry.