Objective To explore the relationship between perceived stress and suicidal ideation as well as the mediating effect of resilience and depression.Methods A sample of 875 college students was recruited for the study to complete a set of self-report measures of Chinese Perceived Stress Scale(CPSS),the Resiliency Scale of University Students,Suicidal Ideation Questionnaire,and Beck Depression Inventory(BDI).Results ①College students'perceived stress and depression had significantly positive correlation with their suicidal ideation,while the students'resilience had a significantly negative correlation with their perceived stress and depression.②Perceived stress did not affect suicidal ideation of the college students directly,but indirectly affected their suicidal ideation through three significant mediating pathways:the separate mediating effects of(a)resilience and(b)depression,and the serial mediating effect of(c)resilience and depression.Conclusion Resilience and depression exert a chain mediating effect between perceived stress and suicidal ideation of college students.