By constructing an index system, this study analyzed the temporal and spatial characteristics of the economic resilience of 20 resource-based cities in northeast China after the financial crisis in 2008. On this basis, a mediation model was introduced to explore the mechanism of population shrinkage affecting economic resilience. The results show that: (a) from 2009 to 2019, the trend of the economic resilience of resource-based cities in northeast China was “ascending–descending–stable”. As time went by, the spatial difference of the economic resilience of resource-based cities gradually became obvious, indicating that the number of medium- and high-class cities was increasing. (b) By applying a correlation analysis, it was found that both a significant weak correlation and medium correlation existed between population shrinkage and economic resilience during the periods of 2011–2019 and 2013–2019. (c) Six mediation factors, namely industrial output, population consumption, resource dependence, urban innovation, cultural construction and environment quality, were chosen to apply the mediation model of population shrinkage affecting economic resilience. Among them, industrial output, population consumption, urban innovation, and cultural construction exerted a partial mediation effect on the process of population shrinkage affecting economic resilience, while the meditation effects of resource dependence and environment quality were not significant.

The global economic downturn and the new normal status of China’s economy have revealed that the Northeastern region of the country is facing challenges due to poor adaptability and weak regional economic resilience. In regard to the regional cities of China’s municipal-administered county system and from the perspective of the relationship between the economic resilience of the central-cities and the outer-suburbs, it is helpful to explore the characteristics of the regional economic resilience in Northeast China from 2007 to 2018. We find that: (1) The economic resilience of the central-cities and outer-suburbs in Northeast China has deteriorated. Compared with the central-cities, the economic resilience of outer-suburbs has weakened even more. (2) The types of regional economic resilience of the central-cities and outer-suburbs of Northeast China have diversified and weakened. The main types of economic resilience have changed from city-prospered-suburb-prospered and city-balanced-suburb-prospered to city-balanced-suburb-balanced and city-declined-suburb-declined. There are differences in the types of municipal economic resilience that are affected by changes in the economic resilience levels of central-cities and outer-suburbs. (3) It is further confirmed that the industrial structure has an important influence on the resilience of the regional economy. The economic resilience of the outer-suburbs in the Northeast China appear to be more vulnerable and more heavily influenced by changes in the proportion of the secondary industry than the central-cities.