Poplar mosaic virus (PopMV) is one of the most harmful viruses of forest trees. It has worldwide distribution- it is present in all countries where poplar is grown, and causes severe losses in wood production quantity and quality. Control is based on the use of healthy propagation material. Determination of virus-infected trees is particularly important in the case of trees for propagation, because the virus infected cutting is the most important method of PopMV transmission and spreading. In 2009. 27 poplar leaf samples were collected from trees with symptoms of possible virus infection. Detection of Poplar mosaic virus (PopMV) was conducted by DAS ELISA test with serological kit of Loewe Biochemica GmbH. From 27 samples, in 13 (48.1%) the PopMV was successfully detected. Infected trees showed symptoms of mosaic, chlorosis, diffuse yellow spotting, yellow ringspots and red necrosis of leaf veins. According to previous studies, poplar can be freed from PopMV by heat treatment.