The human capital investment can be decided by the method using real time interest rate to calculate discount value.If the capital which is needed to invest is smaller than discount value which is used as expected earnings,the investment in human capital is clever.Human capital investment risk can be avoided by enlarging human capital investment,rational and effective combination of human capital and incentive policy and regulations.The carrier of human capital investment is human beings who have subjective initiative.If the investment is wanted to be successful,economic methods should be used to make correct investment choices and the persons including their subjective initiative who are cultivated by the investment should be sufficiently made use of.