Background: Centenarians have been the fastest growing population worldwide. However, this group has been less studied in developing countries. China, as the first country in the world to age before getting rich, has provided a unique setting to study centenarians in developing areas. This study aimed to investigate the current sociodemographic characteristics, health profiles, and social relationships of Chinese centenarians. Methods: We used a census-based approach to conduct face-to-face survey in April 2017 with centenarian residents in Suixi County, the first Intrenational Healthy Longevity Area in China. A total of 100 centenraians were involved, including 67 females and 33 males. Information of socioeconomic and demographics characteristics, quality of life (physical, cognitive, and psychological function), and social support and relationships was collected. Sex differences in each measure were examined. Findings: We find that good self-reported health, good life satisfaction, intact memory function, independence, and unsatisfied healthcare needs were reported by 24.4%, 45.9%, 31.6%, 46.3%, and 33.4% of the respondents, respectively. Subjective symptoms among males were less prevalent (p<0.05). There were no statistical significant sex differences in cognitive and psychological function. The major source of care provision has been family. Generally, the centenarians had intimate relationships with families but maintained distant relationships with friends and communities. Interpretation: Our results bring attention to family-based care to provide informal care, and health education to promote healthy behaviors and healthcare utilization, for the oldest-old in China. The findings also imply a crucial role of good relationships with family in exceptional longevity. Funding Statement: This study was sponsored by Shanghai Science and Technology Committee (Grand No. 16DZ2344000) Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: This study was conducted as a joint collaboration between the Sixth People’s Hospital Affiliated to Shanghai Jiaotong University and the Affliated Hospital to Guangdong Medical University. Ethical approval was obtained from local health authorites in Guangdong Province before the survey began. The study was conducted in compliance with the ethical standards of the ethics committee of Guangdong Medical University. Informed consent was obtained from all respondents.