Previous research has demonstrated negative associations between task-relevant conflicts and collaboration. To supplement the previous findings and explore the potential benefits of conflicts, we differentiate between two types of task conflict expressions (i.e., mild vs. intense task conflicts, such as debates vs. disagreements regarding work-related issues) in dyad interactions and propose the differential effects of mild versus intense task conflicts on collaboration based on the theory of conflict expression. In three studies with experimental manipulations and surveys on working adults, the results demonstrated that perceptions of debates versus disagreements (in Studies 1 and 2) or mild versus intense task conflicts (in Study 3) enhanced perceivers’ collaboration with others via the perceivers’ assessments of others’ openness rather than emotions. The findings regarding positive associations between mild task conflicts and collaboration implicate the coexistence of conflict and collaboration. Moreover, the results showed that debates versus disagreements (in Study 1) or mild versus intense task conflicts (in Study 3) achieved high task performance by enhancing perceptions of others’ openness that subsequently increased collaboration. These findings clarify why conflicts inconsistently influence interpersonal interactions and task performance.