As China′s economy enters the new normal, the traditional development momentum advantage is no longer available. "Green innovation", as the integration point of "innovation driven" and "green development", has become an effective means to break through the constraints of environment and resources and promote sustainable development. Clarifying the driving factors of urban green innovation and identifying the contribution of different factors play an important role in urban sustainable development. This paper uses the 2005-2016 Chinese patent full-text database to identify the number of green patents at the prefecture-level city level, and uses regression method to identify the main determinants and their contribution to the differences in regional green innovation levels. 

This paper finds that: (1) From the perspective of the development level of Green Innovation: the level of green innovation in China shows the obvious characteristics of unbalanced development among regions. The overall development of the eastern region is relatively rapid, while that of the central and western regions is relatively slow. The green innovation output of different cities shows polarization. The smallest city has no green innovation output, while the largest number has reached 11070 green invention patent applications. (2) From the perspective of driving factors: there are differences in the factors that affect green innovation output in different regions. The marginal influence of innovation input factors on green innovation output in the eastern region is more obvious, while the green innovation output in the central region is jointly affected by economic development indicators, innovation input factors and government behavior, while the green innovation output in the western region shows the characteristics of government behavior leading, and the proportion of the second and third industries has significant positive effect on the green innovation in the western region. (3) From the perspective of contribution decomposition, different factors have different contributions to green innovation in different regions. Among them, the level of economic development is the main factor that affects the inequality of innovation and development among regions. As a direct factor that affects innovation output, innovation input plays a decisive role in the impact of green innovation. At the same time, the government′s behavior has obvious regional characteristics, and its contribution to the central region is more obvious. 

According to the analysis results of this article, the policy recommendations are as follows: (1) Strengthen cross-regional green innovation exchange and cooperation. On the one hand, while further developing green innovation in the eastern region, it should increase the radiation effect on other regions, and use its own advantages to promote green and innovative development in the central and western regions. On the other hand, the central and western regions should increase green innovation. Innovative investment, make full use of abundant resources and technological advancement advantages, learn from each other′s strengths, and strive to narrow the gap with the eastern region. (2) Formulate a factor-driven policy that integrates with the actual situation of the city to improve the level of urban green innovation. For the eastern region, in order to stimulate the further development of green innovation, science and technology R&D investment and talent introduction should be strengthened; for the central region, while increasing scientific research personnel and capital investment, it should further deepen fiscal decentralization and strengthen regional economic development; To promote the further increase of green innovation output in the western region, we should vigorously strengthen the development of the secondary and tertiary industries in the western region, and at the same time expand the new space for economic development, focusing on the economy to promote the coordinated development of green innovation. (3) Establish and improve a guarantee system for coordinated development of green innovation among regions. The local governments in the central and western regions should continue to strengthen their support for local green innovation development, and use the guiding role of regional policies to promote higher-quality development of green innovation; while the eastern region should follow the development characteristics of a market economy and release it by improving market-oriented institutional mechanisms. Green innovation vitality promotes high-level development of green innovation.