The droughts that have occurred in recent years and the lack of water resources require determining the water requirements of agricultural products to manage water resources properly. This research aimed to determine the water requirement of potato crops in different climates of Kermanshah province during the 2021-2022 cropping season. Kermanshah province can be generally classified into three climates: cold, moderate, and hot. The largest areas of potato cultivation in these climates are in Sonqor, Kermanshah, and Qasr-e-Shirin cities, respectively, which were selected as research sites. A total of 35 farms were selected based on farmers' conditions, and field measurements were conducted during the growing season. The water requirement of potatoes was determined using data from the nearest synoptic meteorological stations to the selected farms and the Penman-Monteith method. The results showed that the average length of the potato growing period in Sonqor, Kermanshah, and Qasr-e-Shirin cities was 134, 137, and 148 days, respectively. The average water requirement of potatoes in these cities and the overall average across the three cities were 630, 718, 454, and 605 mm, respectively. The water requirement of potatoes in Qasr-e-Shirin was 25% lower than the average in the three regions of Kermanshah province due to growth during the cooler months of the year.