Trends in the cost of grassland utilisation were assessed bearing in mind economic, ecological and environmentally friendly management of grassland in mountain regions. The cost calculations were based on the results of long-term trials carried out within the research on grassland management techniques aimed at production, and the quality of hay. A computer program (MACHDATA www.ktbl.de) was applied to specify the technological cost of making hay from permanent (PG) and oversown (OG) grasslands. The direct and the total costs of production and quality of hay dry matter (DM) were calculated by a modified specific calculation formula. On the basis of the grassland management technology (permanent and oversown grasslands), the direct and total costs were calculated per ha, per metric tonne of hay DM, per a unit of production of protein and energy nutrients, respectively. The yield of hay DM increased with rising fertiliser rates, the highest yield was recorded at the highest fertiliser rates, namely 7.29 t ha-1 at PG and 6.79 t ha-1 at OG. The total costs ranged between 139.39 and 409.38 € ha-1 at PG and from 174.37 to 444.72 € ha-1 at OG fertiliser treatments, respectively. The least efficient production of hay DM and crude protein was recorded at PG with P and K fertiliser application. The application of NPK fertilisers (Treatments 3 and 4) on PG and OG reduced the total costs of production of protein and energy nutrients. The economic effect of oversowing was found at treatments with high fertiliser application rates.