With the development of globalization, the issue of national economic security has attracted much attention.This paper argues that the loss of human capital will threaten the national economic security. Therefore, more attention should be paid to the security of human capital while studying the economic security.In this paper, the negative effects on the national economy development from the loss of human capital is particularly analyzed, base on the evaluation of the situation of the loss of human capital in China. In conclusion, this paper suggests that the government should set up a safeguard system for the security of human capital as soon as possible