this paper, we modeled the climate of Iran for future periods. Each period is a 30-years period centered on a year. The range of periods is from 2000 (i.e., 1986- 2015) to 2100 (i.e., 2086-2115). This was made using 2 General Circulation Models (ECHAM4 and HadCM2) and 18 IPCC scenarios. MAGICC-SCENGEN was used as a tool for downscaling GCM low resolution output data. Result of HadCM2 model shows a % 2.5decrease in precipitation until 2100 but ECHAM4 shows a %19.8 increase for this period. Another difference between results of these 2 models is that HadCM2 predicts an increase in precipitation in next decades for Mazandaran, Golestan, Khorasan Shomali, Khorasan Razavi, Semnan, Tehran and some parts of Gilan and Ghazvin provinces, while ECHAM4 predicts a decrease for that regions. HadCM2 predicts precipitation decrease for southeast of country (Hormozgan, Kerman, Bushehr, south of Fars and some parts of sistan va Baloochestan, but in ECHAM4 that regions will have precipitation increase in similar period. About temperature, both HadCM2 and ECHAM4 agree in temperature increase in next decades for all provinces. These 2 models predict, on the average, 3 to 3.6c increases in temperature until decade 2100. Maximum increase in decadal temperature in ECHAM4 is about 1c more than HadCM2 and both of them are in conformity with each other in spatial distribution of decadal temperature.

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