Noise reduction in the shop-floor is one of the important parts of green manufacturing. In the shop-floor, machine tool is one of the main noise sources. A new approach is discovered by investigation that remarkable noise reduction can be obtained by optimizing the scheduling of parts and machine tools. Based on the discovery, A new method of noise reduction is proposed in this paper. A noise reduction scheduling model in the shop-floor is established, and the application of the model is discussed also. A case is studied, which shows that the method and model are practical with 2.46db noise reduction.