In order to explore the relationship between college students' psychological capital, achievement goal orientation with academic achievement, adopting psychological capital scale for college students, achievement goal orientation scale, and academic achievement scale, the present study made a questionnaire survey among the 567 students from Ningbo University in Zhejiang Province and Guangxi Normal University. The result showed that college students' psychological capital and achievement goal orientation both had significantly predictable functions on academic achievement, psychological capital a significant influence on academic goal orientation, and achievement goal orientation has significantly played a totally intermediary role in the influence of college students' capital psychological capital on academic achievement.