To remedy the limitation of traditional capital structure theory，which takes the financial capital as the core，it is of significance to take human capital into account.The empirical research on the relationship among human capital，financial capital and capital structure shows that，for Chinese hightech companies，the guarantee function of financial capital to human capital is greater than its substitution function currently.Therefore，human capital owners effort level increases along with the increase of financial capital.In addition，companies debt ratio would influence human capital owners effort level as well.The higher the debt ratio，the less effort human capital owner invests.Therefore，maintaining a proper level of financial capital investment will promote an efficient effort of human capital，while it is also significant to coordinate the relationship between human capital and capital structure to enhance cost efficiency and even mitigate the agency problem.