Global climate change as a main factor affecting all ecological components, has been attended by researchers all over the world in the recent years. In this regard for simulating the rainfall, National Centers for Environmental Prediction (NCEP) data, HadCM3 data under A2 and B2 scenarios, CanESM2 data under RCP2.6, RCP4.5 and RCP8.5 scenarios were utilized. This research was performed by adopting the Statistical Downscaling Method (SDSM) at Tabriz synoptic station over 31 years base periods included (1971-2001) and 35 years (1971-2005). According to the results of A2 and B2 scenarios simulation, the monthly rainfall mean will increase by 11.22 and 9.58 mm over the first 30 years period (2010-2039), 11.69 and 12.62 mm over the second 30 years period (2040-2069) and 12.77 and 13.10 mm over the third 30 years period (2070-2099) in the future, respectively. Additionally, the results of RCP2.6, RCP4.5 and RCP8.5 scenarios simulation demonastrated that the monthly rainfall mean will increase by 6.29, 7.59 and 7.53 mm over the first 30 years period , 9.28, 8.09 and 7.43 over the second 30 years period and finally 7.90, 10.50 and 7.08 over the third 30 years period in the future, respectively. We found that the most increased rates of the  rainfall mean under all studied scenarios will happen in March, April and May months due to global warming effects on rainfall amount and patern.