Aim Although sleep disturbance is associated with suicide ideation, underlying cognitive-affective mechanisms that may explain this association are not well understood. The aim of the present study was to concurrently evaluate whether emotion regulation difficulties and distress tolerance explain this association among Iranian university students. Method A total of 679 Iranian university students (66.42% females; Mage = 24.34 years, SD = 4.86) completed a battery of online self-report questionnaire. Structural equation modeling was used to empirically explore the relations among variables. Results Sleep disturbance was positively associated with suicide ideation. Higher sleep disturbance symptoms were associated with higher levels of suicide ideation. Sleep disturbance was indirectly related to suicide ideation through both emotion regulation difficulties and distress tolerance. Conclusion Findings expand knowledge of cognitive-emotional processes that may explain the sleep disturbance-suicide ideation association among Iranian university students. Iranian students experiencing sleep disturbance may benefit from intervention strategies targeting emotion regulation skills and distress tolerance to reduce suicide ideation.