摘要：

Abstract:

【Purpose/significance】 The information asymmetry between governments and social organizations is the key factor that hin⁃

ders the development of government purchase of public services. This paper aims to solve the problems of social organizations hiding

their real ability and realize the information sharing between governments and social organizations.【Method/process】 First, an infor⁃

mation screening model of government purchase of public services under the principal-agent framework is constructed. Second, con⁃

sidering the coupling between blockchain technology and information sharing of government purchase of public service, this paper pro⁃

poses an information sharing mechanism of "blockchain + government purchase of public service". Finally, based on the information

screening model, the information sharing model of "blockchain + government purchase of public service" is constructed to explore its

internal mechanism.【Result/conclusion】 The information sharing mechanism of "blockchain + government purchase of public ser⁃

vice" can not only realize the bilateral information sharing between governments and social organizations, but also improve the govern⁃

ments' revenue and effectively reduce the loss of revenue caused by information asymmetry.【Innovation/limitation】 The information

sharing mechanism of "blockchain+ government purchase of public services" helps government to become a "smart buyer" and en⁃

ables governments to accurately screen service providers.