In laboratory experiments an introduced fish Perccottus glenii consumed selectively tadpoles of three numerous anuran amphibian species of Moscow Province. Perccottus glenii actively consumed all seized tadpoles of the Rana arvalis and R. temporaria. These predators consumed significantly lesser number of Bufo bufo tadpoles and frequently rejected them after seizing without considerable damages. Observations showed that P. glenii rejects B. bufo after intraoral testing. Larvae of dragonfly Aeschna cyanea also actively consumed almost all seized R. arvalis tadpoles, while usually rejected B. bufo after attacking and damaging them. Larvae of diving beetle Dytiscus marginalis sucking out captured prey, intensively consumed tadpoles of R. arvalis and B. bufo and did not reject them.