Gender inequality is a social issue in which access to rights, resources, and opportunities is unequally distributed against certain genders, including women, girls, and other marginalised gender identities, leading to psychological distress. This study exam ined gender inequality and psychological well-being (PWB) among female faculty and staff in higher education institutions (HEIs) in Nigeria. Unfortunately, the effectiveness of efforts to address gender inequality in HEIs and their impact on the PWB of female faculty and staff remain unknown. Quantitative data from well-structured scales measuring gender inequality and psychological well-being were collected from fac ulty and staff across six higher education institutions in Nigeria’s six geopolitical zones. A sample of 240 female academic staff and 240 female non-academic staff participated in the study. Results show that across the six HEIs in the six geopolitical zones, 86 (84.3%) of top management positions are held by men, while only 21 (16%) are held by women. Most faculty (59.8%) and staff (68.3%) report poor PWB due to experiences of gen der inequality. The study found that gender inequality is widespread in Nigerian HEIs, with a significant underrepresentation of women in leadership roles, which contributes to their poor PWB.