Gender inequality remains one of the most persistent forms of social stratification embedded in economic, cultural, and institutional structures. According to the World Economic Forum, Iran continues to rank among the lowest countries in the Global Gender Gap Report 2025, particularly in the domain of economic participation. This study was designed using a qualitative approach based on a grounded theory strategy (Strauss & Corbin, 1998). The study population included female employees with more than five years of work experience, selected through purposive sampling. Data were collected through semi-structured in-depth interviews with 25 participants and analyzed in three stages: open, axial, and selective coding. Causal factors identified included inequality in wages and promotion, behavioral characteristics and low self-confidence, discrimination in access to resources, and discriminatory administrative structures. Contextual factors, such as macro-level government policies, cultural stereotypes, neglect of potential, and job insecurity, also played a role in intensifying this gap. Findings indicated that the core phenomenon is the “reproduction of gender gap in administrative structure and culture”. The study concludes that gender inequality in economic participation is a structural, institutional, and cultural phenomenon.