This study aims to determine heavy metal accumulation levels in the muscles tissues of two economically most important demersal fish species in the Eastern Black Sea, Turkey, red mullet (Mullus barbatus) and whiting (Merlangius merlangus), and evaluate the effects of fish species, sampling locations, fishing season and size groups on heavy metal accumulation levels. Chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd) and lead (Pb) concentrations in fish muscle samples were measured with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Co, Zn, As and Cd accumulation levels in both species differed significantly (P<0.05). The metal concentrations of muscle tissues of both species, in general, were higher during summer and autumn. In the study, the differences in concentrations levels of As and Pb in whiting, Co, Cu, and Pb in red mullet muscle tissues were significantly related to fishing locations. The results of metal concentrations were compared with various legal limits such as Turkish Food Codex (TFC 2011), European Communities Commission Regulation (EC 2006) and Food and Agriculture Organization (FAO 1983) and the obtained metal levels of fish muscle tissues of both species were found to be below the limit values which are a threat to human health.