Abstract: In the era of knowledge economy, information flow represented by knowledge cooperation and technology transfer has become the main form of spatial interaction. Therefore, the era we are in today is often called the era of global cooperation or the era of global transfer. The process and result is that the national system, regional system or urban system under the global production network gradually disintegrates and is reshaped in the global innovation network. In information flow, technology transfer emphasizes the market process of spatial interaction. Using the spillover effect of technology transfer in developed countries or regions to serve economic growth and technological progress is the profound experience of China′s reform and opening up in the past 40 years. It is also the core support for the country to develop the economy of the central and western regions and build the national technology transfer system. The spillover effect of technology transfer is one of the core issues in economics and management. In the 1960s and 1970s, with the continuous development of economic globalization and global trade with transnational corporations as the leading force, the spillover effect of technology transfer of transnational corporations and its relationship with the economic development of the host country have aroused widespread concern. It is generally believed that technology transfer through investments of transnational corporations can not only realize the technical and economic benefits of the investing country, but also can drive the technological and economic development of the host country through knowledge spillover. The existing research on technology transfer mainly focuses on technology transfer, industry- university cooperation of technology innovation subjects or specific industries represented by universities and multinational companies, and the measurement indicators are mostly based on the innovation output data. While few attentions have been paid on the relationship between technology transfer and city economic growth. In addition, there are two aspects in the direction of technology transfer: technology agglomeration and technology diffusion. It is of great theoretical and practical significance for the construction of national technology transfer system to make clear the technological and economic growth stage of Chinese cities. Based on data mining from National Intellectual Property Office of China, the spatial spillover effects of technology transfer depicted by patent transfer in China city system and its impacts on city′s economic growth were sketched using lots of spatial econometric models. We found that in the past 15 years, from 2001 to 2015, China′s city technology transfer showed strong geographical proximity and spatial agglomeration, and the spatial trend of evolution from "multi-polar" to "one superpower and multi-powers" was developed. The Yangtze River Delta region has grown into the most active region of technology transfer in China city system. The spatial econometrics models showed that the contribution of city technology transfer to city′s economic growth is constantly improving. From 2001 to 2015, the development path of China′s city technological economic had gone from the agglomeration economy to the diffuse economy. This paper makes several important contributions to the literature. First, this paper proposes a theoretical framework for studying the relationship between technology transfer and city economic growth, and decomposes urban technology transfer into two dimensions, agglomeration and diffusion. Secondly, this paper identifies the stage of technological economic growth and its evolution path of Chinese cities, which provides theoretical guidance for Chinese cities to develop economy in the era of knowledge economy, that is, to realize technological economy, they must first improve the technological output capacity of cities.

Key words: technology transfer, city economic growth, spatial agglomeration, spatial spillover effect