The aim of this study was to analyze the accumulation of nonylphenols (NPs) and nonylphenol ethoxylates (NPEOs) in the muscles, liver, and bile of flounder (Platichthys flesus), cod (Gadus morhua), and eels (Anguilla anguilla). The flounder and cod were caught in the Gulf of Gdańsk (the Baltic Sea), while the eels were sampled in the Vistula and Szczecin lagoons (the Baltic Sea) and in the inland waters of the Masurian Lake District. NP concentrations in muscles were low in all the samples analyzed and ranged from 14.2 to 28.2 μg-1 kg ww. In contrast, a wide range of NP concentrations were observed in livers, which seemed to depend on both the species and the feeding status of the fishes. NP levels in flounder and eel livers were from three to twenty times higher than those in the muscles, but they were below the limit of quantitation (LOQ) in all the cod liver samples. The mean concentration of NPs in the liver of flounder caught in the Gulf of Gdańsk was 222 μg kg-1 ww, while in that of the eel ranged from 57 μg kg-1 ww in fish caught in the Masurian Lake District to 519 μg kg-1 ww in eels caught in the Vistula Lagoon. NPs were detected in bile in only a few eel samples, which indicated that bile analysis has limited applications for estimating NP contamination in marine fish. The NPEOs in all the samples analyzed were below the LOQ.