Against the deficiency of the sole internal incentive mechanism of indentification of high-tech enterprise under the background of financing constraints， it manually collated the data of government's qualification of high-tech enterprises， and took A-share listed companies between 2008-2018 as the sample， and used the propensity score matching method （PSM） to investigate the feasibility and effectiveness of the external financing incentive mechanism of indentification of high-tech enterprises in alleviating financing constraints and promoting their innovative development. The result shows that under the financing constraint scenario， the external financing incentive mechanism of high-tech qualification recognition has additional incentive effect on innovation performance and operating performance of enterprises； and the greater the financing constraints faced by enterprises， the more significant the incentive effect is. The further analysis finds that the external financing incentive effect of identification of high-tech enterprises is more significant in regions with higher degree of financial marketization， the samples of non-state-owned enterprises and small and medium-sized enterprises. The conclusion expands the theoretical research boundary of financing constraints， deepens understanding of the mechanism of selective industrial policies affecting industrial development， and has certain reference value for the government to demonstrate the influence of various policies rationally.