Abstract: The uncertainty principle, put forward by W. K. Heisenberg in 1927, includes the uncertainty relation between two mechanical quantities and uncertainty relation between energy and time. It makes the quantum mechanics to have an integrated mathematic description and a solid physical base. In this paper, we introduce the background, the process of uncertainty principle presented, and the applied aspect of the uncertainty principle. The important role of the debate in the science developing is stressed.

Key words: uncertainty principle, Copenhagen school, science developing