During reading instruction, sustaining learners' reading motivation (RM) may be a challenge but a requisite when the goal is to keep learners reading. In the context of the present study, it was examined as to how RM may be sustained in a reading course. For this purpose, information on learners' RM was collected in a semester-long university reading course with 118 Korean learners of English at the pre- and post-instructional stages of reading. RM was assessed with "Motivations for Reading Questionnaire" before and after reading instruction. Results indicated that "reading involvement" had decreased for all learners whereas the less skilled learners demonstrated an increase of "reading efficacy" and a drop in "reading for grades." A linear multiple regression further indicated that "reading efficacy" was a significant predictor of reading proficiency only for the skilled learners. Implications are presented on how reading needs to be conducted by allowing learners to choose their own materials, which in turn may have an effect on developing more robust forms of RM.