Psenopsis cyanea (Alcock, 1980) was found to be one of the most dominant species in the deepsea catches of FORV Sagar Sampada from the west coast of India. This paper encompasses the geographical and vertical distribution, abundance, feeding, spawning biology and length weight relationships of P. cyanea collected from FORV Sagar Sarnpada and commercial boats operated along the continental slope of the south west coast of India. Spatially it was found abundant at lat. 11° to 12" N and vertically at 201-300 and 301 - 400 m depth zones. Females dominated irrespective of seasons or depth. It exhibits a seasonally synchronized reproduction due to the presence of mature adults during the late pre monsoon and early monsoon which is confirmed by the recruitment of the juveniles during late monsoon. Prawns were found to be the principal food item followed by fishes. 'b' values showed negative deviation from the isometric growth with increase of depth as 3.3039 and 1.7933 in the depth zones 201-300 m and 301-400 m respectively. The length range of the exploited stock varied from 13.6 to 21.6 cm with a distinct mode at 16.6-17 cm both in male and female followed by 16.1-16.5 cm in female and 17.6-18 cm in male. The major part of the harvested stock belonged to 15 to 19 cm length group which appeared as the commercial size group of this species.