The resource rich countries in Gulf witness an acute income inequality among various segment of population. Therefore, this study is an attempt to examine effect of oil and gas resources on aggregate and disaggregated income inequality in 6 GCC countries such as Bahrain, Kuwait, Oman, Saudi Arabia, and UAE from 1980 to 2020. The estimated result of aggregate analysis reveals that the rent from oil and gas resources are major source of acute income inequality in GCC countries. While the disaggregate analysis shows that the increase in oil and gas rent increase income of top 1 and 10 percent, whereas reduces income share of 40 and bottom 50 percent significantly. The findings thus validated the prevalence of Dutch diseases phenomena and urges GCC countries to diversify resource wealth for development of other sectors to enhance equitable income distribution.