Recently more and more attention is being paid to pollution of the environment by microplastics. The problem is well recognized in marine and surface water in Western Europe. There are also well-documented studies on removal of microplastics during wastewater treatment in Germany, Finland, Denmark, Canada and Norway. So far the problem has not been identified in Eastern European countries, including Poland. Because of this, it is of high importance to evaluate the scale of problem also in these countries. The paper presents the results of preliminary studies on microplastics content in influents, effluents and sewage sludge of selected wastewater treatment plants in southern Poland. It was stated that content of microplastics in influents was in the range from 19.4.103 to 552.2.103 particles per 1 m(3), in effluents from 28 to 960 particles per 1 m(3). Microlitter particles removed from raw wastewater were accumulated in sewage sludge. Total concentration of microplastic particles in the sludge was in the range from 6.7.103 to 62.6.103 particles per 1 kg d.m. In liquid phase, finer fractions of microplastics were dominant. In sewage sludge larger particles, especially fibers, were effectively cumulated. About 95%-99% removal efficiency of microplastics from influents was stated. No correlation has been found between the wastewater flow rate and the content of microplastics in influent, these problems require, however, more detailed analysis of microplastics chemical composition and mass.