The service industry is becoming greater importance in the current economy. The service quality has become an important competitive factor in service industry. Until now, 6 sigma method has well accomplished in manufacturing industry. 6 sigma method has been applied to the service industry to improve service quality, but it has not been reported that 6 sigma method is a successful method for service industry to improve service quality. In this paper, we suggest a MAVIC model to improve service quality. It is a model which is combined with advantages of a SERVQUAL model and 6 sigma method. We has proved its effect with applying a MAVIC model to real service techniques.