Students reporting symptoms of posttraumatic stress disorder (PTSD) and depression are at increased risk for suicidal ideation, putting them at greater risk for suicidal behavior and attempts. Perceived social support is a robust protective factor against the impact of PTSD and depression on suicidal ideation in college students, however different forms of social support (family, friends, significant others) may have greater influence on this association. In the current study, the influence of the different types of perceived social support on the relationship between PTSD-depression symptoms and suicidal ideation in college students were examined. College students ( = 928; 71% female) were recruited in part of a cross-sectional survey study examining the role of mental health on education functioning. A hierarchical regression indicated that PTSD-depression symptoms (b = .27, < .001) and perceived family support (b = -.04, < .01) were significantly associated with current suicidal ideation, while perceived support from friends (b = -.02, = .417) and significant others (b = -.01, = .301) were not. Perceived family support interacted with PTSD-depression symptoms (b = -.03, < .05) to weaken the positive influence of symptoms on current suicidal ideation. Perceived family support appears to be the significant component of social support that moderates the relationship between PTSD-depression symptoms and suicidal ideation. Future research should focus on strengthening family support as a potential mechanism to mitigate suicide risk among college students who may be away from their families for the first time.