<p>This study uses data from the 2020 wave of the China Health and Retirement Longitudinal Study to examine multidimensional well being among adults aged 45 years and above in Jiangsu and Gansu, two provinces with distinct development profiles. The index draws on twelve indicators covering education and cognition, lifestyle risk, health status, economic support, and social security. Equal weights are assigned across dimensions, while entropy weights are used for the indicators within each dimension. Missing values are imputed using Multiple Imputation by Chained Equations, and the estimates are pooled across the imputed datasets using Rubin’s rules. Socioeconomic inequality is assessed with the Slope Index of Inequality and the Relative Index of Inequality based on household consumption rankings. Although the two provinces record very similar overall composite scores, the pattern beneath those scores differs. Jiangsu shows a clearer advantage in health status, while Gansu displays a modest relative strength in economic support and social security coverage. The most pronounced socioeconomic gradient appears in education and cognition. The lifestyle dimension moves in the opposite direction, especially in Gansu, where lifestyle related risk is relatively higher among groups with higher household consumption. Under the baseline specification, women show slightly higher composite scores than men, though this difference becomes less stable once the dimensional specification is changed. What matters here is not simply that the provincial averages are close, but that the underlying composition of well being and its distribution across groups are not the same. Looking across dimensions makes these differences easier to see and helps identify where inequality is most concentrated.</p>