Abstract: Family-state isomorphism is an important concept in understanding Chinese traditional culture.This paper interprets the “structure” in the family-state isomorphism as a stable differential structure perceived respectively in the private and public life of agents,which,as seen from the perspective of trust,at the end of the “family” is manifested by the differential mode of association from family members to outsiders,and at the end of “state” is manifested by the differential trust from the central government to the local government.The structural similarity between these two kinds of differential order constitutes the isomorphism between the family and the state.Interpreting the family-state isomorphism as the same kind of differential order has its cultural and institutional basis.The former involves the parental metaphor for the head of the higher-level government,and the latter involves the vague cognition of the evaluation of government’s behavior.Using the statistical data of the China Social Credit System Survey (CSCSS),this paper shows the basic situation of the family-state isomorphism in contemporary China and its formative mechanism.