The Indian mackerel, Rastrelliger kanagurta forms 5-40 % of the marine fish landings along the Dakshina Kannada coast. The paper deals with the fishery, biology and stock assessment of mackerel landed by trawlers along this coast. The mackerel landed were in size 145-275 mm and the length-weight relation was W = 0.00000138481 L ^^^^ Growth parameters estimated were L = 281.67 mm and K = 1.233. Based on these estimates and mean values of M 1.696, F 2.9226 and Z 4.6186 with current effort, yield is 452 t per annum at E 0.63. The MSY has been calculated as 530 t for an effort factor of 6.0 indicating that further increase in effort can bring in more mackerel.