The object of this paper is to evaluate a working environment noise at manufacturing process of metal material products. To accomplish the object; An employee noise exposure criteria, which is mounted in big size enterprise, was investigated. The noise at the 460 points of the manufacturing process machine in the 38 processes of the 1 factories were measured. The database of the noise was built from the measurement data. The major sound sources and frequency range for the manufacturing process of metal material product machine was investigated. In this study, we compare working environment noise criteria of korean with employee noise exposure criteria