This study aims to examine the impact of customer service as a mediating factor in the relationship between the physical environment of hair shops and customer satisfaction, and to propose strategies for improving the quality of customer service along with enhancing the physical environment of hair shops. Data were analyzed using the SPSS 27.0 program, with a total of 541 questionnaires, and all empirical analyses were verified at a significance level of 5%. The analysis of the mediating effect of customer service in the relationship between the physical environment and customer satisfaction showed that the sub-factors of the independent variable, physical environment—namely aesthetics, newness, convenience, and accessibility—had a statistically significant positive (+) effect on the mediating variable, customer service, in the first stage, thus fulfilling the mediation condition. In the second stage of the mediation condition analysis, it was found that the sub-factors of the independent variable, physical environment—namely aesthetics, newness, convenience, and accessibility—had a statistically significant effect on the dependent variable, customer satisfaction, thus fulfilling the mediation condition. The results of the three-step mediation analysis showed that the regression coefficients for the independent variables of aesthetics, newness, convenience, and accessibility were significant and decreased compared to the second step. Additionally, the mediating variable of customer service was also found to be significant, indicating that customer service meets the conditions for partial mediation in the relationship between the sub-factors of the physical environment—namely aesthetics, newness, convenience, and accessibility—and customer satisfaction. As a result, the managers and staff of the Hair shop realized that they should prioritize customer satisfaction, improve service quality, and manage the physical environment well in order to encourage positive word-of-mouth.