Sajna, V.H.; Zacharia P.U.; Liya, V.B.; Rojith, G.; Somy, K.; Joseph, D., and Grinson, G., 2019. Effect of climatic variability on the fishery of Indian Oil sardine along Kerala coast. In: Jithendran, K.P.; Saraswathy, R.; Balasubramanian, C.P.; Kumaraguru Vasagam, K.P.; Jayasankar, V.; Raghavan, R.; Alavandi, S.Indian oil sardine (IOS), the commercially and ecologically important pelagic fish of the Kerala coast is susceptible to climatic variation. The study analyzes the impact of climate change on the catch of Sardinella longiceps along the Kerala coast and tries to predict the catch trend under the two RCP scenarios 4.5 and 6.0 for the period 2020-2100. Monthly catch of IOS by major gears for the period 1990-2016 was collected and Relative effort (Effort) and Weighted CPUE (cpue) were accordingly estimated. The climatic variables Sea Surface Temperature (SST), Precipitation (Pr), Chlorophyll a (SSC) and Salinity (SSS) were obtained from NOAA/NASA. The relationship of cpue and Effort of IOS to environmental variables were explored by Generalized Additive Model. The best fit model was selected using lowest Akaike information criterion (AIC) value, Deviance and F statistic. Predictions of cpue and Effort under RCP 4.5 and RCP 6.0 were done and the catch of IOS was estimated. The GAM model revealed the variations in the catch of IOS in relation to climate change. The SST, SSS and Pr showed a negative relation whereas SSC was found to be positively related to the catch of IOS. The results of the study indicate a decreasing trend of cpue and catch and an increasing trend of Effort towards 2100 under both climate change scenarios. ADDITIONAL INDEX WORDS: Climate change, CPUE, generalized additive model, Indian oil sardine, Kerala coast, RCP.