Abstract: Aiming to investigate the relationship between the rural middle studentsgrit and academic achievement and the mediating effect of their academic procrastination, as well as the internal psychological mechanism, we surveyed 337 rural middle school students by the Short Grit Scale, the Middle School Students' Academic Procrastination Questionnaire and the Academic Achievement Questionnaire. The investigation indicated the following results: (1) The questionnaire scores of the rural middle studentsgrit, academic procrastination and academic achievement questionnaire showed significant difference in terms of demographic variables such as the grade of students and the education level of their parents, as the grit score of high-grade students was lower, the procrastination score was higher and the academic achievement was lower. The students whose parents had taken higher education had higher score on grit, lower on academic procrastination and higher on academic achievement. The grit score was also affected by family income as the students with higher family income showed significantly higher grit. There was also significant gender difference on the rural middle studentsacademic procrastination and academic achievement. The academic achievement score of male students lower than that of the female students, and the academic procrastination higher. (2) The rural middle studentsgrit was significantly negatively correlated with their academic procrastination and was significantly positively correlated with their academic achievement. (3) The academic procrastination plays a fully mediating role in the relationship between the rural middle school studentsgrit and academic achievement. The results suggest that the middle school students' grit has a positively predictive effect on their academic achievement, and the full influence can be achieved by reducing their academic procrastination.

Key words: grit, academic procrastination, academic achievement, mediating effect