Perccottus glenii Dybowski, 1877 is one of the freshwater fishes listed in the IAS list of Union Concern as an important invasive alien fish species. In Ukraine, it was recorded for the first time in the 1970s and now is widespread in all Ukrainian large river basins. Chinese sleeper from eight localities was studied: seven from the Dnipro River basin and one from the Siverskiy Donets River basin. In total, 403 specimens were examined. Standard length of Chinese sleeper in our samples varied from 10 mm to 143.6 mm. Total weight varied from 0.05 g to 79 g. The largest female had a standard length of 138.6 mm. The biggest male had a standard length of 143.6 mm. Chinese sleeper become mature at age 1+ with a length near 40 mm. Males predominated in all samples. Immature specimens were dominating in five samples, while mature fish prevailed only in two samples. The a values varied from 0.000012 to 0.000059. The growth coefficient (b) ranged from 2.68 to 3.19.
