Work engagement is a core indicator that reflects the quality of teachers’ occupational lives and the development of students, but few studies have explored the connection between strengths use and work engagement of teachers and the mechanisms underlying this relationship. This paper aimed to investigate how the relation of strengths use with work engagement is affected by a teacher’s satisfaction of basic psychological needs. For this purpose, 648 teachers in China completed questionnaires. The results revealed that strengths use exhibited a positive correlation with work engagement and needs satisfaction. Furthermore, autonomy, competence, and relatedness satisfaction mediated the effect of strengths use on work engagement for teachers. The results suggest that autonomy, competence, and relatedness satisfaction serve as factors that mediate the effect of strengths use on work engagement. The significance and limitations of the study are discussed.