In fact, the service industry has had a huge impact in the economy of many countries, including the UK and Vietnam. Regardless of the economic crisis in previous years, the hospitality industry in both these countries is recovering slowly. Offering superior service quality could benefit the hotel in many aspects such as gaining competitive advantages or increasing customer satisfaction. Furthermore, the globalization has created more opportunities for people to travel abroad. Thus the target customers for the hospitality industry is not only domestic visitors but also international ones. To sum up, it is important for hotel managers to understand service quality perceptions of different nationality customers to conduct segmentation strategies and to provide service that are appropriate with specific groups. The main goal of this study is to measure British and Vietnamese customers' expectation and perception of service quality of hotels in their own countries. Then all results from the UK study are compared to Vietnam one to clarify there are any significant differences between British and Vietnamese guests about expected and perceived service quality. The results show that expected service quality level of Vietnamese customers is higher than that of British while the later has a higher perception than the former. While the service quality of the UK hotel is consistent at a high standard, Vietnam hotel should improve many aspects of service, especially assurance, responsiveness and reliability. To conclude, the study suggests the essential factors of service that British and Vietnamese hotel managers should concentrate to achieve competitive advantage and attract more both domestic and foreign guests.