Regional inequality in the process of economic growth has recently been a popular topic. This paper creatively proposes contribution decomposition methods to divide various regions' contributions into economic contribution and population contribution. The methods consider not only economic growth but also population change, which may be more effective than the traditional method that uses the per capita GDP (gross domestic product) as its single measurement indicator. Moreover, the objective is to take a step forward and reveal the spatio‐temporal evolution characteristics of regional disparities by integrating barycentre model and economic development equilibrium model. Lastly, the applicability of the research method proposed in this paper is verified by a case study of Jiangsu province, China; the results show a new regional economic pattern in Jiangsu province. [ABSTRACT FROM AUTHOR]