The paper presents the history of restructuring process of coal mining industry in Poland as well as its present state. In the aspect of expected decrease of demand for Polish coal the possible activities of the industry to keep the profitability of production are searched. The paper shows how the unit cost of sold coal depends on the level of production. The analysis employs the theory of fixed and variable costs. In unfavourable external conditions of decreased level of production and falling down coal prices, the possibilities of further decrease of costs of sold coal are explored in the paper.