The Pearl River Delta (PRD) is the global city-region in China’s southeast coastal areas and aims to create a comprehensive cross-border region across divergent institutional systems. The city-region in China has been long deemed as the engine of the regional growth in the past four decades. This article draws upon the theory of “new state space” to investigate the two regional projects in PRD, that is Shenzhen-Shanwei Special Cooperation Zone and Sui-Guan-Shen (Guangzhou-Dongguan-Shenzhen) intercity railway projects. By examining the theory of “new state space” from the lens of rescaling, we build up a conceptual framework capable to understand the rescaling of city-regional governance in post-reformed China. Based upon crises of capital accumulation and administrative governance, this article is committed to tracking the upscaling and downscaling of powers in regional governance and the overall rescaling processes of relations between provincial and local governments. In general, this article develops a China-contextualized conceptual framework and two empirical cases to problematize the rescaling of regional governance, both of which are central to shed lights on the rationale of China’s political economy. Three major findings are reported as follows. First, in the industrial collaboration project, in order to overcome the crises of weak institutional framework for intercity cooperation, provincial government is devoted to injecting resources, devolving administrative powers, deregulation, and empowering great autonomies to localities. These actions constitute to the downscaling of regional governance. Second, in the large-scale infrastructure project, in order to overcome the lack of the financial authority, provincial government is committed to building strong bargainer through horizontal power reconfiguration, recentralizing the developmental power from localities compulsorily, and delivering actual incentives for power recentralization. These actions constitute to the upscaling of regional governance. Third, considering the above-mentioned findings, this article argues that rescaling of regional governance in PRD is a flexible and polydirectional rescaling process, which is differentiated by concrete regional projects, rather than a unidirectional and mechanical rescaling process as suggested by conventional literature.