The Japanese blunthorn lobster, Palinustus waguensis was landed at Chennai's trawl landing centre by deep sea trawlers operating along the Tamil Nadu coast in February, April, August and September 2004. The specimens collected were in the size range of 32 - 48 mm carapace length (CL) in February and 53 - 75 mm in August. The females sampled were all in an advanced state of maturation, with ripe ova, in both the months. The length-weight relationships were derived as W = 0.000265 L^3.24 for males and W = 0.000244 L^3.23 for females.