The Key Factors of Service Marketing Mix in Tourism Accommodation regarding the 4-5 Stars Hotels in Thailand Nutteera Phakdeephirot College of Tourism and Hospitality, Rangsit University Pathumthani, Thailand nutteeraphakdeephirot@gmail.com ABSTRACT As Thai economy continues to alter from a manufacturing to a service direction. The service sector is fundamental for the national income and national employment, its influence to the growing of gross domestic product (GDP) fluctuates. Tourism service is one of service sectorial classification list of World Trade Organization (WTO). WTO had define tourism and travel-related services includes services provided by hotels and restaurants (including catering), travel agencies and tour operator services, tourist guide services and other related services. This study investigates the customer behavior toward Service Marketing Mix (7Ps) in tourism accommodation and subsequently to test the hypothesis: the customers have a diverse attitude of 7Ps in 4-5 stars hotel in Thailand. Quantitative and qualitative methodology exploit in this research, data collect by survey technique. The result of study will contribute the advantage for the 4-5 stars hotel in Thailand to realize the average achieve of each 7Ps signify its strength and weakness to develop the value of Service Marketing Mix afterward to augment the consumer satisfaction. Keyword: Customer Behavior, Service Marketing Mix, Tourism Accommodation, 4- 5 Stars Hotels, Thailand Introduction Tourism is a significant sector for Thai economic, a statistic of the ministry of tourism and sport of Thailand showed in 2015 more than 29.9 million international arrivals traveled around Thailand, it generated 32.7 billion dollar US, and offering several million employments direct and indirect in this segment. Travelers always demand the lodging to stay or take a break, therefore accommodation is a principal element of tourism sector, and the hotel is one of the different categories of tourism accommodation. The figure from Tourism Authority of Thailand demonstrate in 2016 more than 1.67 million tourism accommodation throughout Thailand, 60 percent characterize as the hotels and resorts and the number of the hotels in Thailand increase each year.