-The large public scientific organizations -we call in this paper multi-institute scientific organizationsalways play important roles in the national innovation systems, and undertake basic research, applied research, some science frontier research and the research of emerging areas like nanotechnology. To examine the behaviors of these large public scientific organizations is important for monitoring the development of a nation's scientific strategy and evolutionary of science and technology. This paper focuses on five important public scientific organizations in nanotechnology, and compares their scientific behaviors. The results show that although they all develop rapidly in nanotechnology, they have different foci and different collaboration behaviors.