The study was aimed at the determination of the effect of afforestation of post-arable light textured soils with Scots pine on their enzymatic activity. The study was conducted in the area of the Wysoczyzna Lubartowska region (SE Poland). Ten paired sites of afforested soils (five with 14- to 17-year-old stands and five with 32- to 36-year-old stands) with adjacent cultivated fields, and five sites of natural forest with the presence of tree stands ca. 130-150 years old were selected. Soil samples were taken from the whole thickness of humus (A) and B horizon and, in the case of A horizon of the afforested soils, from three layers of 0-5 (AI), 5-10 (AII) and 10-20 cm (AIII). The activity of dehydrogenases, phosphatases, urease and protease was determined. It was observed that pine stands after more than thirty years of growth caused a decrease in the activity of urease and phosphatases, and an increase in the activity of dehydrogenases. In the soils of 32- to 36-year-old stands the activity of urease was more similar to the natural forest soils than to the arable soils. Conversely, in the case of dehydrogenases it was still more similar to the arable soils. With respect to phosphatases and protease no clear relationship was noted. The results show that enzymatic activity of soil can be used as an indicator of changes in the properties of post-arable soils after their afforestation.