Here were reported clinical features of silent infected COVID‐19 patients. Our study showed that the prevalence of the silent infection of COVID‐19 is 5.8% (95% CI: 3.4‐9.9%), which is much higher than 1.2% which from the report in China CDC. The silent infection patients were more likely to be young adults, the patients without chronic disease. All of the cases in the presented study was found because they were traced as close contact of confirmed cases. Our study indicated that traced the close contract of confirmed case, long time self‐quarantine, and screening is necessary to prevent the secondary cases in community