This study aims to identify and analyze the key challenges and barriers that hinder effective public participation in the urban renewal projects of deteriorated areas in Tabriz. The central issue lies in the low level of citizen engagement in redevelopment initiatives, which often face stagnation or failure due to a lack of attention to social and institutional contexts. The research adopts a mixed-methods approach. In the qualitative phase, semi-structured interviews were conducted with 20 urban planning experts, and data were coded using thematic analysis in MAXQDA. In the quantitative phase, data were collected from 256 property owners with registered plots within the deteriorated areas and analyzed using SmartPLS. The qualitative findings revealed 9 main dimensions and 41 sub-indicators, including regulatory frameworks, lack of social capital, weak oversight, limited capacity building, and absence of participatory precedents. Structural regression analysis indicated that all hypothesized paths were statistically significant, with the highest path coefficient belonging to "regulations and policies" (beta = 0.699, t = 13.698). The coefficient of determination (R²) for the dependent variable "public participation" was calculated at 0.642, indicating that the model explains 64.2% of the variance. All variables met normality assumptions, and reliability indices (Cronbach's alpha > 0.70) confirmed internal consistency. In conclusion, achieving meaningful public participation in the renewal of Tabriz’s deteriorated urban fabric requires institutional reform and the restoration of public trust at the neighborhood level.