Pomatoschistus marmoratus (Risso, 1810) is a small demersal fish and one of the dominant species inhabiting shallow waters of the Mediterranean. Information, however, on their feeding habits are still scarce. In this study, the stomach contents of P. marmoratus were investigated in order to determine feeding habits according to seasons and sizes. The fish were collected monthly from 3 stations between October 2008 and August 2009, using a beach seine, from the shallow waters of the Canakkale Strait, Turkey. A total of 383 P. marmoratus, ranging from 13 to 69 mm TL, were analysed. The most important prey items in the stomach contents were copepods and amphipods. The numerical abundance of each food item in the stomach contents varied significantly with season. The diet of juvenile P. marmoratus consisted mainly of copepods. The occurrence of largest prey items such as amphipods and bivalves appeared relatively higher in adults. However, no significant differences were found between the feeding habits of juveniles and adults.