Because the scale of SMEs is small, they have weak anti-risk abilities, and a lot of small and medium-sized enterprises are given to birth around the world each year while at the same time many of them are closed down. Therefore the SMEs need to improve their own innovative abilities urgently. This paper first describes the innovative advantages of the SMEs. And then it focuses on studying the innovative capabilities of the SMEs in both China and United States. After doing the research work we found that the SMEs of United States have outstanding advantages in innovation. It is just like what the President of United States has ever noted in his annual report------?? The technological innovations of small businesses are the main forces of why United States has been in the leadership position of world economy." The small and medium-sized enterprises of United States are mainly distributed in the knowledge-intensive industries which have relatively high-tech and strong innovative features. The overall innovative level of Chinese SMEs is not high. Chinese SMEs are mainly distributed in the labor-intensive or resource-intensive industries in which low value-added products are produced. Therefore the innovative level of Chinese SMEs is much lower than that of United States'. Finally this paper puts forward some countermeasures and suggestions that are helpful to enhance the innovative capabilities of Chinese SMEs.