The proximate composition, fatty acids and amino acids profile as well as mineral composition of frozen fillets from Pangasius catfish (Pangasius hypophthalmus) imported to Poland (PP), Germany (PG) and Ukraine (PU) and fillets from Nile tilapia (Oreochromis nilotcus) imported to Poland (TP) and Germany (TG) were investigated. PU contained ten times more fat than PG and PP. Tilapia fillets contained higher levels of n-3 fatty acids and showed more preferable n-6/n-3 ratio than pangasius fillets. The fillets of PG contained higher levels of protein and essential amino acids than PU and PP, however the amino acids composition of pangasius and tilapia fillets was similar for all specimens. The fillets of PP and PU contained significantly higher amounts of sodium than other studied groups, which suggests that they were subjected to additional treatment to increase their water holding capacity. The results show significant differences in the nutritional composition of pangasius depending on their place of import, thus it was recommended that more information regarding the nutritional composition of the frozen fillets sold through self-service freezers should be provided for the final consumer.