Groundbreaking part of natural complexes of the Republic of Belarus nowadays is capable of the secondary succession after decline of anthropogenic influence. The part of the disturbed lands along with abandoned lands increases annually. Changes of the structure of succession phytocenosis cause transformation of enthomocomplexes and insect populations. For revealing of the main mechanisms of the formation of enthomocomplexes in opened succession systems it is necessary to evaluate functional dependencies between entomophage and their hosts. Therefore, investigation of insect populations in transformed opened ecosystems against the background of climate change appears an important direction of the research. The main goal of the article is evaluation of the dynamics and number of wasps of different families, living on upland meadow within secondary succession. The research have been carries out on the territory of Beresina national Reserve for the period of 1985, 1987-1989 and 2011. Total of 1676 specimens of wasps belonging to164 species from 8 families (Chrysididae, Mutillidae, Pompilidae, Scoliidae, Crabonidae, Tiphiidae and Vespidae) have been collected with a help of Malaise traps. The analysis of successional changes in communities structure at the level of families and specific level is given.