Background The COVID-19 confirmed cases TRANS overseas continue to rise for months, while people overseas prefer to return at present. It is risky to have a large number of infected imported cases which may cause COVID-19 spread to China and even lead to outbreak again. In order to prevent imported infection MESHD, Shenzhen implemented the losed-loop management strategy by taking nucleic acid testing (NAT) for severe acute respiratory syndromes MESHD coronavirus 2 (SARS-CoV-2) and medical observation for 14 days among individuals who have epidemic history (Hong Kong, Macao, Taiwan province and other countries) within 14 days. Our study described the status of COVID-19 infection MESHD among entry people in Shenzhen, and also evaluated the effect of closed-loop management strategy.Methods A total of 86,844 people overseas entered Shenzhen from January 1 to April 18, 2020, and there were 39 imported cases. We made a descriptive study by analyzing the entry time, reported time, local confirmed cases TRANS in origin countries, and the number of entry people from abroad. The NAT were completed in Shenzhen center for disease MESHD control and prevention (CDC), ten district-level CDCs, as well as fever MESHD fever HP clinics.Results The infection MESHD rate of entry people was 4.49‰ (95% CI: 3.26‰ − 6.05‰). Most of the entry people or imported cases have Chinese nationality. The number of entry people and imported cases in Nanshan and Futian districts were larger than others. 15.73% of the entry people came from the US, and 12.67% came from the UK. 14 imported cases (35.9%) came from the UK, 9 (23.08%) came from the US. The imported risks from the US and UK in Shenzhen were higher than other countries or regions. According to the 14-days’ incubation period TRANS and the number of entry people, individuals from the US since Mar 9 were the high-risk population. Accordingly, entry people from the UK since Mar 13 were the high-risk population. It is important to evaluate the imported risk by analyzing local confirmed cases TRANS status in origin countries or regions and the number of entry people from these countries or regions to Shenzhen. The distribution of entry time and report time for imported cases in Shenzhen were similar. So it is important to prevent and control COVID-19 imported infection MESHD by taking NAT and medical observation at port.Conclusions It is effective to implement closed-loop management strategy for individuals who have epidemic history (Hong Kong, Macao, Taiwan province and other countries) within 14 days. In order to control COVID-19 outbreak, we need the collaboration and cooperation at the global, national, and subnational levels to prevent, detect, and respond effectively.