To date, women are under-represented in most positions of authority, including sport leadership, not only in Poland, but also in most countries worldwide. Until recently, there has been no research on gendering of positions within Polish sports federations. The presented analysis employs Acker’s theory of gendered organization (1990, 1992) to explore professional experiences of men and women in positions of sport leadership in Polish national sports federations. The findings, based on 24 in-depth interviews, revealed that gender-based practices maintain gender imbalance in the studied organizations. The studied male leaders demonstrated a significant degree of sexism in their statements and justified gender inequalities by referring to biological essentialism. Further, the assumptions regarding masculinities as associated with leadership positions, liminal gender awareness and gender role stereotyping are the major obstacles faced by women in Polish national sports federations.