The constant growth of human capital is the essential force of Economic growth. The deep research on private investment in urban and rural human capital in Guangxi is necessary for developing economy and narrowing urban-rural gap. Through the analysis on the historic statistics, it is found that there were disparities total quantity and investment structure of private investment in human capital of urban and rural residents. By using the ELES model, the marginal investment trend, investment demand, elastic income, own-price elasticity and mutual-price elasticity of private investment in human capital of urban and rural residents are analyzed. It is pointed out that income is the key factor that affects the private investment in human capital of urban and rural residents. In Guangxi, the private investment and marginal investment in human capital of urban and township residents are higher than that of rural residents ;the own-price elasticity and mutual price elasticity of rural residents' private investment in human capital are ail higher than that of urban residents'.