Abstract: The study determined socio-economic factors influencing yield of arable crops in Osun State. Primary data were collected from 150 arable crop farmers from 5 cells in each of the three agricultural zones in the state using purposive and random sampling methods. The data were analysed with descriptive statistics and regression techniques. Result of the analysis showed that the mean age of arable crops farmers was 52 years, the mean years of formal education was 9 years with household size of about 11 and mean farm size was about 3.5 ha. The yield of arable crops slightly increased in 1998 to 2000. Multiple regression analysis showed that R and R2 for all the variables investigated was 0.687 and 0.472, respectively. Training and demonstrations attended by farmers with Beta Coefficient of (0.123) was the best factor-influencing yield of arable crop in Osun State. Other factors in descending order are access to agricultural input (0.119); farm size (0.052) and age (0.042) Agricultural policy effort should be directed at increasing agricultural extension activities to farmers and agricultural input should be made available at affordable prices to arable crop farmers to increase their yield.