As ecological and environmental challenges intensify globally, countries are increasingly prioritizing the enhancement of green innovation capacity. While existing research has primarily examined the influence of external factors--such as financial development and industrial upgrading--on green innovation, the role of internal drivers and their interactions with external factors remains underexplored. The expansion of higher education has generated a significant pool of highly skilled talent, which serves as an intrinsic driver of green innovation capacity. Drawing on 3,348 panel observations from 31 Chinese provinces between 2011 and 2022, this paper employs STATA to conduct panel econometric analyses--including two-way fixed effects models, moderation analysis, and spatial Durbin models--to examine how the scale of higher education influences green innovation capacity. It further explores the moderating roles of industrial structure upgrading and financial development, as well as the spatial spillover effects and heterogeneity of this impact. The results indicate that the scale of higher education significantly enhances green innovation capacity but produces negative spatial spillover effects on neighboring regions. Furthermore, both industrial structure upgrading and financial development act as positive moderating factors in this relationship. Heterogeneity analysis reveals that the effect of higher education scale on green innovation capacity is more pronounced in the eastern region and at the undergraduate level, relative to the central and western regions and specialized levels. This study clarifies the intrinsic connection between higher education and green innovation, offers evidence to optimize educational resource allocation and tailor green development policies, and provides policy insights to support global efforts toward education-driven green transformation and the achievement of the Sustainable Development Goals (SDGs).