The novel coronavirus (COVID-19) infection has spread worldwide since late 2019. People who have social contacts with COVID-19 patients might be at higher risk of physical or mental health problems. This study investigated whether people who had social contacts with COVID-19 patients would have poorer physical or mental outcomes, and different attitudes and behaviors. Chinese adults were recruited to fill in an online survey using snowball sampling during 21st-26nd February 2020. Physical symptoms, psychological outcomes, quality of life, COVID-19 related attitudes, and behaviors were measured. The differences in the outcomes between participants who had COVID-19 social contacts and those who had not were analyzed. The survey included 1,447 non-infected eligible participants. Among those, 173 (12.0%) reported at least one confirmed/suspected case in their social contacts. In the multiple regression adjusted for demographic data, the presence of confirmed/suspected infection cases in one's social contacts was significantly associated with poorer physical and mental outcomes, lower health-related quality of life, and different COVID-19 related attitudes and behaviors (p<0.05). In conclusion, people who had social contacts with COVID-19 patients were at risk of adverse health outcomes. Future studies are needed to understand the long-term impacts. Similarly, strategies to improve health outcomes for these people are needed.