Drought is one of the most destructive weather events that causes significant damage to human life. One of the regions that has experienced mild to very severe droughts in recent years is Kermanshah province in western Iran. Therefore, the aim of the present study is to investigate the severity, frequency, and trend of drought in Kermanshah province. For this purpose, two indices, SPI and PNI, and Mann-Kendall, Senn, and Petit tests were used to investigate the stations of Kermanshah province. The results showed that the severity, duration, and percentage of drought occurrence in the studied stations were not the same, and the distribution of drought intensity-duration-frequency can be affected by climate, differences in the direction of elevation expansion, and the type and direction of entry of rain-generating systems. Based on the Petit test, only the three-month SPI in the Sonqor and Mahidasht stations and the six-month and twelve-month SPI for Mahidasht had a breaking point, which occurred in 2016. Based on the results of the two Mann-Kendall and Senn tests, there is a significant trend in the SPI-3, SPI-6 and SPI-12 series for Mahidasht station in all three SPI intervals. The trend of land use change, the increase in farmers' tendency to cultivate water crops in recent years and the increase in groundwater resources extraction are among the factors that directly and indirectly affect the drought trend and have caused the drought trend to increase in all three intervals or some time intervals despite the increasing trend of rainfall in some stations. Also, climate change and the occurrence of long-term droughts can be among the factors that, despite the decreasing trend of drought in Ravansar, QasrShirin, Gilangharb, Sonqor and Paveh stations, the rainfall trend to decrease in these stations.