J. Inf. Technol. Appl. Manag. 26(1): 1~19, February 2019 ISSN 1598-6284 (Print) https://doi.org/10.21219/jitam.2019.26.1.001 ISSN 2508-1209 (Online) 4G Adoption : A Survey of Vietnam Market Tommi Tapanainen*․Trung Kien Dao**․Thanh Hien Nguyen***․Thi Thanh Hai Nguyen**** Abstract The aim of this study is to assess the impacts of service properties, price expectancy, social influences, and switching costs on adoption intention of 4G in Vietnam. The research model was established by the theory of diffusion of innovation, technology acceptance model, service quality, social influences and switching costs. The result from customers using telecommunication services in Vietnam shows that adoption intention of 4G is affected directly by perceived usefulness, personal innovativeness, price expectancy, social influences, prior service quality and switching costs. Whereas, switching costs have negative effect on adoption intention. Other factors such as personal innovativeness, perceived ease of use and prior service quality have an indirect effect on adoption intention of 4G. Keywords：Adoption Intention, Switching Costs, Price Expectancy, Social Influences, TAM Received : 2018. 12. 15. Revised : 2019. 02. 04. Final Acceptance : 2019. 02. 08. ※ This work was supported by Pusan National University Research Grant, 2017. * Corresponding Author, Department of Global Studies, College of Economics and International Trade, Pusan National University, 2, Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241, Republic of Korea, Tel：+82-51-510-3007, e-mail：tojuta@gmail.com ** School of Economics and Management, Hanoi University of Science and Technology, e-mail：kiendtcoco@gmail.com *** International Development Studies, Palacky University, e-mail：hiennt115@gmail.com **** Department of Information Studies, Abo Akademi University, e-mail：thinguye@abo.fi