[Purpose/significance] This study aims to reveal the characteristics and influencing factors of mobile APP users' privacy risk retention behavior from the perspective of privacy uncertainty, explaining the paradoxical phenome⁃non where users choose to bear losses caused by privacy risks rather than actively adopt privacy protection measures. It contributes to strengthening user privacy security protection and optimizing the mobile application ecosystem. [Meth⁃od/process] Based on grounded theory method, this study explores the characteristics and influencing pathways of mo⁃bile APP users' privacy risk retention behavior. [Result/conclusion] Under the perspective of privacy uncertainty, mo⁃bile APP users' privacy risk retention behavior manifests as three characteristics: active privacy concession, default pri⁃vacy permission, and forced privacy compromise. Such behavior leads to intensified risks, risk addiction, and cognitive rigidity. At the user level, platform level, privacy benefit level, and social environmental level, ten factors influence the occurrence of privacy risk retention behavior. User privacy uncertainty plays a mediating or moderating role in the path⁃ways through which these factors affect privacy risk retention behavior.