Abstract: In order to clarify the mechanism of action of government spending on science and technology on economic benefit，the 31 provinces，autonomous regions，and municipalities directly under the central government of China in 2018 are taken as the research objects. A spatial Quantile Regression model and a spatial intermediate effect test model are constructed to analyze the direct and secondary effects of government spending on science and technology on economic benefit. The findings are as follows：firstly，government spending on science and technology can significantly facilitate the improvement of economic enefit；in provinces of middle and lower levels，the R&D expenditure can strongly facilitate the economic benefit，while in provinces of middle and higher levels，the intensity of R&D expenditure can strongly facilitate the economic benefit. Secondly，the spatial spillover effect of government spending on science and technology can still promote economic benefit；the higher economic benefit a region has，the easier it is for the region to be affected by the government spending on science and technology of neighboring regions.Thirdly，economic development and urbanization play an intermediation role between government spending on science and technology and economic benefit；and the secondary effect of government spending on science and technology on economic benefit through economic development is stronger. Fourthly，between the government spending on science and technology of different economic zones and economic benefit，there is an evident phenomenon of level differentiation which is mainly manifested as the southeast coastal economic zone >the northern coastal and northeast economic zone>the middle economic zone>the greater southwest economic zone> the greater northwest economic zone.

Key words: government spending on science and technology, economic benefit, spatial spillover effect, regional economic growth, spatial quantile regression