This study examines the causal relationship between green digital finance and technology diffusion using panel data from 35,532 'citing city-cited city' pairs over 14 years (2002-2015). The research employs an extended spatial Dubin model with dual-weighted boundaries and distances to account for both administrative boundaries and geographic distances. Key findings include: 1. **Spatial Stimulus Effects**: Green digital finance significantly stimulates technology diffusion, particularly in terms of spatial diffusion across cities. A 1% increase in green digital finance leads to a 16.89% increase in the probability of patent citations and a 28.06% increase in the number of patent citations. 2. **Mechanisms of Diffusion**: The digital economy and market integration play crucial roles in facilitating technology diffusion. Digitalisation innovation has a better mechanism effect than other factors, and market integration, whether through trading flows or intensity, enhances the positive impact of green digital finance on technology diffusion. 3. **Direction of Diffusion**: The diffusion effect from east-region cities is better than that from central-west cities. Even within the east region, cities cite more patents from other cities in the same region, indicating a strong diffusion effect from economically prosperous areas. 4. **Hypotheses and Policy Implications**: The study supports Hypothesis 1, suggesting that green digital finance overcomes localization barriers and promotes technology diffusion. Hypothesis 2 is supported by the mechanism analysis, showing that green digital finance promotes technology diffusion through the digital economy. Hypothesis 3 is also supported, indicating that green digital finance facilitates technology diffusion by promoting market integration. The study concludes with policy recommendations to synergize green financial and technological innovation policies, optimize transmission channels, and enhance the ability of technologically underdeveloped areas to receive and apply technology.This study examines the causal relationship between green digital finance and technology diffusion using panel data from 35,532 'citing city-cited city' pairs over 14 years (2002-2015). The research employs an extended spatial Dubin model with dual-weighted boundaries and distances to account for both administrative boundaries and geographic distances. Key findings include: 1. **Spatial Stimulus Effects**: Green digital finance significantly stimulates technology diffusion, particularly in terms of spatial diffusion across cities. A 1% increase in green digital finance leads to a 16.89% increase in the probability of patent citations and a 28.06% increase in the number of patent citations. 2. **Mechanisms of Diffusion**: The digital economy and market integration play crucial roles in facilitating technology diffusion. Digitalisation innovation has a better mechanism effect than other factors, and market integration, whether through trading flows or intensity, enhances the positive impact of green digital finance on technology diffusion. 3. **Direction of Diffusion**: The diffusion effect from east-region cities is better than that from central-west cities. Even within the east region, cities cite more patents from other cities in the same region, indicating a strong diffusion effect from economically prosperous areas. 4. **Hypotheses and Policy Implications**: The study supports Hypothesis 1, suggesting that green digital finance overcomes localization barriers and promotes technology diffusion. Hypothesis 2 is supported by the mechanism analysis, showing that green digital finance promotes technology diffusion through the digital economy. Hypothesis 3 is also supported, indicating that green digital finance facilitates technology diffusion by promoting market integration. The study concludes with policy recommendations to synergize green financial and technological innovation policies, optimize transmission channels, and enhance the ability of technologically underdeveloped areas to receive and apply technology.