The study discussed advanced-level Korean high school EFL learners’ demotivation and remotivation strategies in English learning. Demotivation refers to specific external forces that reduce or harm motivation; remotivation is the process of recovering the reduced motivation. Although both are common in L2 learning, only a few studies address this issue. Using the survey data of 130 participants, the study identified eight demotivating factors through factor analysis. The first factor, negative attitude toward English, indicates that even high school students felt demotivated because of the sheer difficulty of studying English. Descriptive statistics revealed that a negative attitude toward the English-speaking community was not a strong demotivator, which indicated that students possessed Machiavellian motivation. Correlation and regression analysis suggested that no demotivator had a significant negative relationship with English scores; rather, the ways students perceived the demotivators were more important. Eight remotivation strategies were identified; among those, “Keep thinking about the social importance of English” was the most often mentioned one. These results suggested the need for further qualitative, systemic research on remotivators and for training programs for practicing remotivation strategies.