<p>Amidst economic recession pressures, strategically harnessing the coupling effects between sci-tech innovation and the digital economy is crucial for achieving global sustainable development. This study explores the dynamic interplay between sci-tech innovation and the digital economy, particularly focusing on their coupling nexus. The coupling coordination between innovation and the digital economy in China is shifting from slight incoordination to primary coordination, as indicated by the coupling coordination degree model. High-quality coordination is geographically concentrated along the eastern coastline, which accounts for approximately 7% of the total provinces. Decomposition of the Gini coefficient reveals that inter-regional disparities contribute most significantly to overall variation, contributing over 60%, while intra-regional differences account for more than 24%, and the impact of transvariation intensity is minimal. Furthermore, the outcomes of the spatial Durbin model show the presence of positive spatial autocorrelation in the coupling coordination levels. Key influencing factors, such as investment and government spending, exhibit substantial positive spillover effects. This study deepens understanding of the coupling nexus between sci-tech innovation and the digital economy, offering policy recommendations for countries seeking to optimize the interaction between innovation and digitalization subsystems.</p>