Although there is a growing interest in mobile learning, there are limited studies that focus on student knowledge acquisition. As applications and usages of mobile technology have become more and more accepted, it is important and meaningful that researchers and practitioners of mobile learning understand the potential factors that could influence learning outcomes. Accordingly, the primary purpose of this study was to investigate the roles of mobile technology playfulness, users' resistance to change and self-management of learning in mobile English learning outcomes (MELOs). A case study approach was utilized in this study mainly because the questions of interests were closely related to the usage of electronic dictionaries and their effects on mobile learning outcomes. The participants of this study were all undergraduate students from 10 undergraduate programs of the center for general education at one university in Southern Taiwan. A total of n = 167 undergraduate students with experience using an electronic dictionary to learn English participated in this study. The study results indicated that perceived playfulness and self-management of learning had positive influences on MELO and that users' resistance to change was negatively associated with MELO. (Contains 1 figure and 4 tables.)