In this study biological activity of soils was examined, and the results were interpreted with the use of multivariate statistical analysis – analysis of principal components. The material for the investigation consisted of 52 samples taken from humus levels of chernozems situated in Grzęda Sokalska region (south-east part of Poland). In the soils the activity of the following soil enzymes was marked: alkaline phosphatase, dehydrogenase, and catalase. Statistical analysis of principal components was used to separate one factor that comprised activities of the analysed soil enzymes. This method allowed to simultaneously explain nearly 87% of observed variability of these attributes. Calculating synthetic variable value for each analysed object and group them depending on their agricultural use. Also, the analysis of enzyme activity of chernozems was performed, depending on their geographical location – 4 ‘islands’ where chernozems occurred in the area of Grzęda Sokalska were singled out and characterized.