Objectives:To explore the relationship between freshman’ depression and their suicidal ideation, as well as the intermediary, and regulatory of the opinion to suicide behavior between them. Methods:by using the Symptom Checklist 90 (SCL-90), Questionnaire of suicide attitude (QSA), and Questionnaire for Suicidal Ideation to survey 1395 freshmen. Results: (1)There was significant correlation between depression and suicidal ideation, between depression and the opinion to suicide behavior, as well as between opinion to suicide behavior and suicidal ideation. (2)The pinion to suicide behavior has intermediaryeffects between the freshmen’ depression and their suicidal ideation. Conclusion: It is concluded that the opinion to suicide behavior can partly buffer the effect of the freshmen’ depression on their suicidal ideation.