Sepia aculeata and Sepialla inermis are two species of cuttlefish, which occur widely in South East Asia. This appears to be the first study of the reproductive biology and feeding habits of these cuttlefishes in Myanmar waters. Samples of these two economically important cuttlefishes, S. aculeata and S. inermis were collected monthly from C9 and C10 fishing grounds of Myanmar costal water and their reproductive stages were examined. A total of 30 specimens of each of the two cuttlefishes were collected monthly and their length weight and reproductive status were investigated from August 2013 to August 2014. The body weights of females were significantly heavier than that of males in both species. The 50:50 sex ratio did not differ during the study period. Gonad Somatic Index (GSI) of males ranged from 0.5 to 1.4 while it varied from 2.1 to 4.1 in females among the two species. Eggs were found throughout the study period. The relative fecundity ranged from 55 to 320 eggs per gram. According to the results, the species was a prolong breeder since oocytes and spermatocytes were found throughout the study period but high spawning of two species were found from October to March 2013.