This article analyzes to what extent gender culture affects gender gap in employment. Drawing on Italian data, we measure culture by building two indices: one based on individuals' attitudes, as done in the existing literature; one based on firms' attitudes. Firms' beliefs, which express their set of ideas, values and norms, though generally neglected, are as important as individuals' attitudes to explain female labor market outcomes. Using an instrumental variable analysis, we show that our index of gender culture based on firms' attitudes is significant in explaining gender gap in employment in Italian provinces. We show that the same holds when culture is measured with reference to individual attitudes. (JEL code: J16).