One of the most effective ways to deal with the water crisis and increase the quantity and quality of production in the agricultural sector is to pay serious attention to the water requirements of agricultural products. The purpose of this research is to determine the water requirement of the wheat crop in different climates of Kermanshah province in the crop season of 2021-2022. In a general classification, Kermanshah province has cold, moderate and hot climates. According to the statistics of the 2019-2020 crop year and in the mentioned climates respectively Sonqor, Kermanshah and Sarpol Zahab cities, have the largest cultivated area and were chosen as the research areas. A total of 34 farms were selected under the conditions of the farmers and field measurements were carried out during the growing season. The water requirement of wheat was determined using the FAO Penman-Monteith method and the data of the nearest synoptic meteorological station to the selected farms. The results showed that the average length of the wheat growth period in Sonqor, Kermanshah and Sarpol Zahab cities was 271, 250 and 177 days, respectively. The average water requirement of wheat in the mentioned cities and the average of these three cities were 650, 727, 483 and 616 mm, respectively. The water requirement of wheat in Sarpol Zahab city was 22% lower than the average value in the three regions of Kermanshah province due to the length of the short growth period and the growth in the cool months of the year.