Abstract:In order to explore the boundary of government development expenditure in the process of industrial agglomeration affecting energy efficiency,the regulatory mechanism and threshold effect of government development expenditure in the process of industrial agglomeration affecting energy efficiency from both theoretical and empirical perspectives is verifid.The results show that:firstly,In theory, government development expenditure has a moderating effect in the process of industrial agglomeration affecting energy efficiency. The impact of industrial agglomeration on energy efficiency shows an inverted "N" type path with the continuous strengthening of government development expenditure.It shows that too low or too high government development expenditure will lead to the distortion of industrial agglomeration, which can not play its due positive externality, and then inhibit the improvement of energy efficiency. Only moderate government development expenditure can play the due performance of industrial agglomeration and help to improve energy efficiency.Secondly,on the basis of avoiding endogenous problems, it uses the static panel interaction model to verify the theoretical hypothesis that government development expenditure has a moderating effect in the process of industrial agglomeration affecting energy efficiency based on the panel data of 268 prefecture level cities in China from 2004 to 2017.Thirdly, it uses panel threshold model to verify the dual threshold effect of government development expenditure in the process of industrial agglomeration affecting energy efficiency,the threshold values were 0.2517 and 0.2946, respectively.Then, the group econometric regression of different levels of government development expenditure is carried out, and the results are consistent with the inverted "N" path of the impact of industrial agglomeration on energy efficiency in the theoretical analysis.Research shows that too much or too little government development expenditure tends to inhibit the improvement of energy efficiency and moderate government development expenditure is conducive to the improvement of energy efficiency.