This study examined three influential factors of junior college students' learning engagement: (a) intrinsic and extrinsic motivation, (b) career decision-making self-efficacy (CDMSE), and (c) self-regulation. Participants included 206 students enrolled in the secretarial administration program in a junior college in South Korea. The primary research findings are as follows. First, intrinsic and extrinsic motivation positively influenced CDMSE. Intrinsic motivation influenced learning engagement through CDMSE and self-regulation; extrinsic motivation did not. Second, CDMSE influenced self-regulation and indirectly influenced learning engagement through self-regulation. Third, self-regulation had the largest effect on learning engagement. The findings highlight the need to examine and enhance students' self-regulation skills and help improve the learning engagement of junior college students. This study confirmed the significance of motivation, CDMSE, and self-regulation for junior college students' learning engagement.