In the classroom setting, social context and self-systems affect student engagement for school success. Students' perceived goal orientation of their teachers and grit influence their engagement in academic learning. However, adolescents' efforts for academic success related to teachers' goal orientation and grit remains under-researched in the context of China. The current study aims to investigate the effect of students' perceptions of their teacher's mastery goal orientation on their engagement, specifically considering the mediating effect of grit (pursuing long-term goals with consistency of interest and perseverance of effort). We surveyed 653 eighth-grade students (mean age = 14.4 years) from 13 secondary schools in rural areas of China. The results of structural equation modeling indicated that perceived mastery goal orientation, consistency of interest, and perseverance of effort had significant positive direct effects on student engagement. Additionally, the relationship between perceived mastery goal orientation and student engagement was partially mediated by consistency of interest and perseverance of effort (consistency of interest showed a stronger effect than perseverance of effort). The study contributes to the understanding of the potential mediating effect of grit in classroom settings.