53 striped surmullet, Mullus surmuletus Linnaeus, 1758 (Teleostei, Mullidae), were collected from the Marmara Sea, Turkey and examined for metazoan parasites in July 2017. The parasitic copepod, Peniculus fistula fistula Nordmann, 1832 (Pennellidae), was collected from all the hosts, both on fins and body surface. This is the second report of this copepod in Turkish marine waters. Although Peniculus fistula fistula was reported for the first time on Coryphaena hippurus Linnaeus, 1758 by Öktener (2008), there was an indefiniteness and doubt about the occurrence of this parasite. This study aimed to confirm occurrence of Peniculus fistula fistula in Turkey and to present revised host list with comments.