Abstract: Masculinity contest cultures (MCCs) are prevalent in male-dominated organizations, with previous research showing the harmful effects for employees. MCCs value competition, aggression, and dominance over cooperation, respect, and diversity, fostering a climate of harassment, discrimination, poor psychological health, and high turnover. Conversely, transformational leadership promotes positive interpersonal interactions. This study examined whether transformational leadership counteracts the effects of an MCC on three outcomes (i.e., psychological distress, microaggressions, and turnover intentions) among Regular Force members of the Canadian Armed Forces (CAF). The findings revealed the negative effects of an MCC on all three outcomes, with the effects of two of these outcomes (i.e., psychological distress and microaggressions) influenced by gender. Whereas the results suggest that transformational leaders can mitigate the effects of an MCC on microaggressions for all members, this mitigating effect on psychological distress was only significant for men. Overall, these findings help inform defence strategies and policies targeting cultural issues.