In contemporary China, despite all the efforts in regulating and institutionalizing labor relations, industrial workplaces still witness pervasive opportunism and distrust. Using two-wave nested workplace surveys, collected from over 280 manufactories in the Yangtze Delta region, and semi-structured interviews of factory owners, managers, and ordinary workers, this study explores migrant peasant workers’ rising radicalism in urban China and traces the social and economic origins of this phenomenon. The authors further examine the role of social ties in shaping migrant workers’ resistance and disobedience, and argue that the effect of social ties may be moderated and constrained by the opportunity structure in the organizations.