Crop damage is a major form of human-primate conflict that not only affects the livelihoods of farmers living close to forest areas but also threatens nonhuman primate conservation. This study aimed to investigate the causes of crop loss and foraging by nonhuman primates in southwest Ethiopia. For the purpose of gathering data, we used a questionnaire and direct observation. We employed simple random sampling techniques to select villages and respondents. From the nine selected villages, a total of 130 household samples were identified for the questionnaire. The primates responsible for crop damage were olive baboons and grivet monkeys. Maize, barley, teff, potatoes, sorghum, and other crops were among those foraged by the nonhuman primate species. Farmland close to the woodland boundary suffered more damage than farmland further away. The total amount of maize damaged by the olive baboons and grivet monkeys in the selected kebeles varied significantly. The majority of the respondents used guarding, and a few of them used scarecrows to protect crops from damage by primates. The highest crop damage occurred in the Atiro Tigre and Arigno Gefere villages, while the lowest occurred in the Sedecha villages. The flowering stage of the maize suffered the most, and the seedling stage suffered the least, from grivet monkeys foraging. The growth of crops that are less edible to nonhuman primates, especially on the forest edges, would lessen crop damage.