By using the input—output method and principal component analysis, this paper did a comparative research on the input—output efficiency of human resources of science and technology among the world’s leading countries, and revealed the actual situation of the input—output efficiency of human resources of science and technology in our country. Among all these seven countries, the input—output efficiency of human resources of science and technology in Japan is the highest, and in China the lowest. There is a significant linear relationship between input and output. And finally, it put forward the thoughts and suggestions about improving the input and output efficiency of human resources of science and technology.