This paper is assessing and developing the customer's service quality of 3C Chain Store's in Taichung. The study tries to elaborate an instrument to measure the customer's service quality in this context. Service quality affects the shopping manner of the customer. Therefore, how to keep the service quality of customer is very important for the management of the company. A total of 350 questionnaires were distributed for customers and 278 valid questionnaires were returned (resulting 79.4 percentage of response rate). Independent Sample T Test and One-Way Analysis of Variance were used for data analysis. The resulting conclusions of this study are listed as follows ( In Digital City-Fengjia Store): 1. Gender variables in service quality were significant difference. 2. Marriage variables in service quality were significant difference. 3. Age variables in service quality were significant difference. 4. Occupation variables in service quality were no significant difference.