Drawing from routine activity theory (RAT), this study explored the antecedents of older adults' exposure to online shopping fraud and evaluated the moderators of the linkage between fraud exposure and victimization. Through a survey of 471 Chinese participants aged 55 and above, we found that older adults who engage in high-risk online behaviors, use insecure networks, frequently encounter promotional advertisements, and regularly shop on live-streaming platforms are at a heightened risk of fraud exposure. Following exposure, those exhibiting excessive trust in Internet platforms and a strong face-saving bias were more likely to incur monetary losses. Our research reframed RAT into a structured two-stage process, with fraud exposure leading to victimization, moderated by guardianship, and highlighted the critical role of cognitive biases among older adults. These findings offer valuable insights for developing effective safeguards to protect older people in the digital shopping landscape.