The present research aims to preserve the quality of seafoods by preventing the occurence of Listeria monocytogenes in the salted rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) stored at different Pinosylvin (3,5- dihydroxy-trans- stilbene) which is known as both a fungicide and a bactericide and inhibits the growth of L. monocytogenes was used as a main substance within the scope of the study. The research was performed at the University of Eastern Finland. The development of artificially inoculated L. monocytogenes in samples stored for 21 days at +3, +8ºC, and 9 days at +20ºC was monitored. Pinosylvin was applied superfically on the samples, and the concentrations was 140 μg/ml. The method of TS EN ISO 11290-2 was used for the detection and enumeration of L. monocytogenes. L. monocytogenes was not detected in the uninoculated controls during the follow up period. There was rapid development of L. monocytogenes in Listeria inoculated samples stored at +3 and +8 ºC, while the L. monocytogenes counts were almost remained at the inoculum level in pinosylvin treated samples. At 20ºC, L. monocytogenes in pinosylvin treated samples was resumed growing and reached the level of Listeria inoculated samples. The research findings demonstrated the inhibitory effect of pinosylvin on the development of L. monocytogenes in the samples. The effect was bacteriostatic (preventing the bacterial growth) but not bacteriocidic. In conclusion, under special circumstances, pinosylvin has the potential to be used for the purpose of preserving the quality of seafood.