As the Smartphone adoption rate increases, Smartphone users pay more attention to mobile payment. There are several options for mobile payment but there is no dominate method. Proximity mobile payment is the newest form of mobile payment. Security, cost, and convenience are three main factors Smartphone users keep in mind when making a mobile payment. This paper investigates Smartphone users perceptions and preferences toward mobile payment methods in Korea and the U.S. U.S. Smartphone users have a willingness to pay more for a secure mobile payment transaction, even though Korean users have more experience in the mobile payment frequency. Among the three factors, mobile security is the factor of strongest influence on mobile payment frequency in both countries
