The sensitivity analysis of three T. aesivum (GW 322, GW 496 and GW 366) and one T. durum (GW 1139) cultivar of wheat was performed to see the possible change in the grain yield of wheat due to changed sunshine hours (BSS), maximum and minimum temperatures using W OFOST model. The potential condition was assumed with congenial weather and adequate management practices. The results showed that the increase in sunshine hours was found to increase the yield in all cultivars and vice versa. The rise in maximum and minimum temperatures had adverse effect on wheat yield. The increase in the maximum temperature by 5°C may cause reduction in yield by 24 to 29%. The effect of the minimum temperature was also of the similar order, but the varietal differences were observed. Among the cultivars, GW 496 was found to be most sensitive to maximum temperature and less to bright sunsh