Abstract This paper aims to explain how to use the generalized method of moments (GMM) analysis technique to estimate the relationship between the gender wage gap and economic development for unbalanced panel data for OECD countries during the period 2011–2021. The results show that an increase of 1% in wage inequality between the two genders leads to a 0.013% decrease in economic development in the case of the OECD. The relationship is statistically significant at 1% which is consistent with previous studies