Reproductive biology of Mediterranean cuttlefish Sepia elegans has been studied in the Aegean Sea from total of 924 animals (432 males, 492 females) caught during monthly trawl surveys from May 2008 to April 2009. Cuttlefishes were measured, weighed, maturity assessed, and reproductive systems were removed and investigated in the lab. The size at maturity (ML50) were 42 mm (males) ML and 41mm ML (females) respectively. Seasonal changes in a gonadosomatic index suggest extended reproductive period of the population with two peaks of spawning; once in July and in October. The ovulation pattern of S. elegans is asynchronous and spawning occurs continuously. The female potential fecundity was 513-1190. The spermatophore counts for mature males ranged 167-486. Size of adult individuals in the East Mediterranean was smaller than that in the Western Mediterranean probably due to lower productivity and high temperatures (hence expenses on metabolism).