This paper studies on the quality problem for the Reley using the 6 sigma process. The application of 6 sigma process suggested reliable and valuable statistical data for the quality of the Relay at the production line. In the measurement step in 6 sigma process, the FMEA(filure mode effect analysis) were used for the detection of problem source. The application of 6 sigma process gave the improving method for the quality of the Relay. Consequently the 6 sigma process was proved very effective for the quality problem reducing at the production line.