Teamwork is common in daily work life, and it is likely that, when working within teams, conflict may occur. Conflict negatively affects a team’s psychological safety – the feeling of safety and willingness to share one’s ideas and take risks while in a team. The gender diversity of a team may moderate this negative relationship. In the present study, I examined the effects of team-level task and relationship conflict on team-level psychological safety, moderated by team gender diversity. Results showed a negative main effect of both types of conflict on psychological safety. However, gender diversity was not found to be a significant moderator. I then examined the proportion of women on a team as an exploratory moderation analysis and found that a team’s proportion of women strengthened the negative relationship between task conflict and psychological safety – the opposite direction of moderation predicted. A discussion follows of a potential backlash effect of women on a team toward other women, exacerbating the already negative effects of task conflict. Future directions and limitations are discussed.