As the fundamental approach to grassroots social governance, the mass line plays a crucial role in promoting orderly governance at the community level. Taking Z Town’s grassroots social governance as a case study, this paper combines its social participation and mass self-governance practices to conduct an in-depth analysis of the existing problems and their causes within the current grassroots governance system. Based on this analysis, a comprehensive evaluation system for mass participation in grassroots governance is established, comprising 15 secondary indicators across three dimensions: platform construction, public awareness, and actual participation. By defining evaluation levels for participation depth and establishing assessment criteria, a material-element extensible evaluation model for measuring the depth of mass participation in grassroots governance is constructed. The 2023 assessment of public participation depth in Z Town’s grassroots governance, based on this material-element extended evaluation model, reveals that both the “Platform Development” (0.1290) and “Participation in Matters” (0.1382) dimensions achieved their maximum values at the “Poor” level. This indicates that Z Town’s grassroots governance should prioritize building public participation platforms and enhancing the effectiveness of public engagement in governance processes.
