This is the first record of the dusky grouper Epinephelus marginatus (Lowe, 1834) in the eastern English Channel. One specimen was caught on 10 June 2011 in the Bay of Seine. It measured 66 cm and weighed 5.5 kg. From the study of internal organs and scales, this specimen was a female of 12 years old that did not grow in the Channel, which confirms the fact of a stray specimen and not the sign of an extension of the distribution with an established population.