Purpose Li-Fraumeni syndrome (LFS) is a hereditary cancer syndrome, characterized by a high risk of developing cancer at various sites and ages. To date, limited clinical benefits of genetic testing for LFS have been demonstrated, and there are concerns about the potential adverse psychosocial impact of genetic testing for LFS. In this study, we evaluated the uptake of genetic testing and the psychosocial impact of undergoing or not undergoing a genetic test for LFS. Patients and Methods In total, 18 families with a p53 germline mutation in the Netherlands were identified. Eligible family members were invited to complete a self-report questionnaire assessing motives for undergoing or not undergoing genetic testing, LFS-related distress and worries, and health-related quality of life. Results Uptake of presymptomatic testing was 55% (65 of 119). Of the total group, 23% reported clinically relevant levels of LFS-related distress. Carriers were not significantly more distressed than noncarriers or than those with a 50% risk who did not undergo genetic testing. Those with a lack of social support were more prone to report clinically relevant levels of distress (odds ratio, 1.3; 95% CI, 1.0 to 1.5). Conclusion Although preventive and treatment options for LFS are limited, more than half of the family members from known LFS families choose to undergo presymptomatic testing. An unfavorable genetic test result, in general, does not cause adverse psychological effects. Nonetheless, it is important to note that a substantial proportion of individuals, irrespective of their carrier status, exhibit clinically relevant levels of distress which warrant psychological support.