The objective of this paper is to better understand the evolution and institutional roots of Hong Kong's growing economic inequality and political cleavages. By combining multiple sources of data (household surveys, fiscal data, wealth rankings, national accounts) and methodological innovations, two main findings are obtained. First, he evidence suggests a very large rise in income and wealth inequality in Hong Kong over the last four decades. Second, based on the latest opinion poll data, business elites, who carry disproportionate weight in Hong Kong's Legislative Council, are found to be more likely to vote for the pro-establishment camp (presumably to ensure that policies are passed that protect their political and economic interests). This paper argues that the unique alliance of government and business elites in a partially democratic political system is the plausible institutional root of Hong Kong's rising inequality and political cleavages.