The objectives of this research were to 1) study the opinions about service quality of customers, 2) study the entrepreneurs approach to improving the quality of service and 3) suggest guidelines development for improving the service quality. The samples were 400 customers who had used services and 2 boutique hotel entrepreneurs on Koh Sichang. The statistical analysis of this study were Frequency, Percentage, Mean, Standard Deviation, t-test and F-test. The research results were found that, 1) Most of the sample customers were male, aged 21-30 years, lived in the metropolitan area, had a bachelor's degree, worked as employee of private company and had an average monthly income between 15,001-20,000 Baht. Their opinions about service quality were high level in every aspects. Customers with different gender, age, domicile, education level and occupations had no difference on level of opinions about the service quality in all aspects. However the different of customer’s incomes had statistically significant difference at the 0.05 level about the service quality in the physical and environmental aspects and personnel aspects. Development 2) study the entrepreneurs approach to improving the quality of service, the results reveal that 8 boutique hotel entrepreneurs on Koh Sichang were trying to find new methods and concepts in providing services to meet the customer needs. 3) Guidelines development, the hotel should create an unique identity, increase the space and create a good environment, fast service, add more channels of customer access, empower employees and increase the security system.