Ahwaz city located in area 8136 square kilometers with population 1338126 people in southwest of Iran in center of Khuzestan province. This city received average 19.56 megajol per square meter per day, average annual sunny day 3088.2 hours, skyline coefficient greater than 0.64 and air transparency more than 0.776 are high potential for use in solar energy systems. In this research, fuzzy AHP and fuzzy TOPSIS methods were used for feasibility of solar power plant. All criteria were selected in 5 sections of geology, environmental, socio-economic, geographic and climate as main and 14 sub-criteria for feasibility of solar power Ahwaz city. Finally, results of fuzzy AHP method showed that climate criterion with weight 0.983, socioeconomic criterion with weight 0.292, environmental criterion with weight 0.646, geological criterion with weight 0.019 and geometric criterion With weight 0.007, have highest and lowest degrees respectively. In total, sub-criteria of temperature, sunshine, radiation intensity, radiation direction, radiation angle, distance from roads, distance from main lines of transmission, surface pollution, distance from city, distance from village, wind, land use, distance from rivers, distance from fault, distance from center earthquake, height, distance from protected areas and latitude and geological formation respectively have highest and least importance. In TOPSIS technique, results also showed that climate criterion with highest score of 1.4831 and then socio-economic criterion with score 1.300, environmental criterion with score 1.120, geological criterion with score 1.088 and criterion Geographically with score 1.028, earned the next rank. As result, the results of two methods are consistent with each other, which indicates accuracy of methods mentioned.