The way appropriate manner and speaking for customers is one of the important things for the people who are engaged in the service industry. With the maturity of society and the market, besides the quality of products, improvement of the service extended to customers is one of the important factors to increase the company’s turnover and profit. Currently in Japan, due to the upsurge of the dental clinics, the dentistry industry as a whole is suffering from severe and excessive competition. In this study, we focus on the dental clinic management in Japan, where the service quality exerts a great influence to the clinic’s outcome. Two dental clinics in Kanto region and three dental clinics in Kansai region were focused and investigated by questionnaire. 1,108 responses were gathered, out of which 898 valid responses, were selected for the analysis, which including 300 male participants and 598 female participants in total. Three categories were investigated by questionnaire, which were basic information, impression evaluation of customer service at each dental clinic, and overall evaluation. The result was showed that a patient who visited a clinic with a fewer times given a higher evaluation of the customer satisfaction level than others respondents. It also was found that recommendation to others by word of mouth can be affected by reception factor, the overall satisfaction level.