Field experiments were conducted at research farm of SKUAST-K, Shalimar campus, Srinagar for 2 years (2003-04 and 2004-05) on silt clay loam soil and at research farm of Integrated Farming System, SKUAST-J, Chatha, Jammu for 7 years (2003-04 to 2009-10) at sandy loam soil in order to find out the impact of climate change on wheat crop under temperate and sub tropical condition by using crop simulation model (DSSAT-v4.0). The results showed that under temperate condition the phenology of wheat is more affected compared to sub tropical condition if temperature increased and decreased. Simulated grain yield of wheat increased up to 18.31 per cent by elevated CO2 to 350 ppm from the base value 330 ppm in temperate condition.