Against the backdrop of accelerated digitalization and the pursuit of high-quality manufacturing development, understanding manufacturing transformation and upgrading from the perspective of productive force restructuring has become an important theoretical issue. Focusing on Guangdong’s manufacturing sector, this paper introduces the concept of digitalization-driven new quality productive forces and develops an analytical framework centered on technological efficiency improvement, factor allocation optimization, and organizational upgrading. The analysis shows that digitalization does not drive manufacturing transformation through simple technological substitution; rather, it reshapes production processes, factor allocation modes, and organizational logics, thereby fostering new quality productive forces and enabling structural and developmental transformation. At the same time, industrial differentiation, institutional heterogeneity, and uneven firm capabilities constitute key structural constraints that define the practical boundaries of this transformation and generate divergent upgrading paths across manufacturing entities. By providing a mechanism-based theoretical interpretation of the relationship between new quality productive forces and manufacturing transformation, this study offers an analytical framework for understanding regional digital manufacturing transformation and yields theoretical insights into the context-specific upgrading of Guangdong’s manufacturing sector.