The object of this paper is to examine the noise generating mechanism at manufacturing process of metal material products. To accomplish the object; A noise generating mechanism of high noise machine, which is mounted in the small and medium size enterprise, was investigated. The measurement method of the noise for the machine by manufacturers were investigated. The noise at the 250 point of the manufacturing procrss machine in the 40 processes of the 3 factories, 3 business fields was measured. The database of the noise was built from the measurement data. The major sound sources and frequency range for the manufacturing processes of metal product machine was investigated.