From the 18^th CPC National Congress till the 19^th CPC National Congress，grassroots governance has been elevated to a strategic height. As the basic units of grassroots governance，the sub-districts and the communities are important venues for implementing the construction of the grassroots governance system and exploring into innovations in grassroots governance models. The key element to strengthen innovations in social governance lies in institution，of which the innovations depend on people whose harmonious coexistence can ensure social peace and order. Compared with the top-down social governance system in China，the sub-districts and the communities are more like miniature “acquaintance societies”，whose organizational levels normally relies on the personal charms of the administrators and constraints of regional folk ethics. In this sense，neighbor regulations and rules play the role of “quasi law” in the grassroots society，making themselves informal systems with the self-enforcement effect. They，who fill the gaps not covered by national legislation，can also be interpreted as a social code of conduct collectively enacted in a democratic process，which enables grassroots areas to realize standardized management and “rule by law” of the community affairs. With the practices of Xinjiekou Sub-district in establishing scientific and rational neighborhood regulations and rules as an example，the article identifies the operation model of the neighborhood regulations and rules and further consolidates the theoretical basis for the necessity of their existence.