Sepia elongata was first recorded from the type shell collected in the nineteenth century. The whole body of this cuttlefish was first described at the middle of the twentieth century from a fixed specimen. Our report provides complementary morphological data. Morphological differences between our measurements and previous ones probably resulted from inter-individual variations. For the first time, behavioral data were collected from field and laboratory observations of living S. elongata. Amongst others, description of body patterns will provide an important tool to accurately identify living S. elongata.