EN
The Sulfur oxidizing bacteria are inseparable involved with very complicated system like soil. They are liable for both the sulfur cycle in the whole nature and for process where the elements are oxidized or reduced. We have to also remember about remarkable role of these bacteria in the pedological process. It seems very important to know better this group of bacteria, especially theirs role in the soil environment and we should perform of the analysis of activity of sulfur oxidizing bacteria in the soil. In this paper, method of the measurement of activity was proposed. This method is based on the analysis of the changes of sulfates in the incubative medium. After this, analysis of the activity of sulfur bacteria in the samples of soil from the two different environments was performed. The samples of luvic soil were collected from the Roztocze region, in the south-east of Poland near by Roztoczański National Park.