The authors investigated the growth of hydromycoflora on the eggs of Chinook salmon (Oncorhynchus tshawytscha) from Małki hatchery on Bystraja River, Kamchatka, Russia. Twenty two straminipilous organisms (fungus-like organisms) were found on eggs of females of Chinook salmon. The most commonly encountered species on the Chinook salmon eggs were Saprolegnia parasitica, S. salmonis, S. ferax, S. diclina, S. hypogyna, Aphanomyces frigidophilus, and Dictyunchus monosporus. However, such species as Scoliolegnia asterophora, Leptomitus lacteus, Pythium diclinum and P. monospermum are rare to salmonid fish. Amino acid, carbohydrate and urease tests were used. All analysed species from genus Achlya, Aphanomyces, Leptolegnia, Pythium and Saprolegnia assimilated alanine, glucose and starch. They did not assimilate glycine, leucine, lysine, ornithine, arabinose and salicin. Urease was assimilated only by specimens from Leptolegnia, Pythium and Saprolegnia genus.