This study examined the analysis of enterprises combination, costs and returns in cassava based farming systems in Osun state, Nigeria. A total of 80 cassava-based farmers were selected using simple random sampling technique during 2007/2008 cropping season. The data were analyzed using Descriptive Statistics, Economic Land Equivalent Ratio (ELER), Net Farm Analysis and Simple Regression Analysis. Generally, all the cassava-based enterprise systems generated higher net farm income per unit of land cultivated than sole cropping of cassava crop. In all combining two enterprises, particularly Cassava + Maize generated the highest net farm income of about N21,514 per hectare. The economic land equivalent ratio with the overall mean of 1.52 showed that the cassava with other crops systems generate higher net revenue per unit of land than sole cassava cropping.