Transhumance is the seasonal movement of pastoralists and their livestock in search of water and feed and there had been a regular occurrence of conflicts between farmers and pastoralists in the country. This research investigates the effect of transhumance pastoralists on farming activities among crop farmers in Oke–Ogun area of Oyo State. Two Local government Areas were purposively selected from the study area due to prevalence and consistent report of pastoralists’ invasion in the area. A total of 50 crop farmers were purposively selected from each local government area to give a total of 100 respondents. Data analysis was carried out using descriptive (frequency counts and percentages) and inferential statistics (Chi-Square). The findings showed that over 90% of the respondents were male and their age ranges between 40-49 years. Majority (94%) had no formal education with very few (4%) having tertiary education. The most cultivated crops in the area included cassava, maize and yam. The average farm size of respondents is 2.5 acres and the farmland was mostly acquired through lease (48%). The most utilised source of labor is family labour (44%). Causes of conflict in the study area included insufficient graze land, use of minor to tender cattle and shortage of water while some of its effects on farming activities included: destruction of farmland, reduction of income and agricultural produce, displacement of farmers and physical attack that leads to accidents and sometimes death. The study therefore recommended that community heads should ensure proper security of community dwellers and grazing reserves should be provided for pastoralists by the government for peaceful coexistence among rural dwellers.