【Abstract】 Objective To investigate the differences of clinical symptoms and chest CT manifestations in coronavirus disease 2019 (COVID19) between imported patients and secondgeneration infection cases. Methods We collected the epidemiological history, clinical symptoms on admission and initial chest CT images of 25 patients with COVID19 confirmed by the positive nucleic acid test from Jan 21, 2020 to Feb 18, 2020 in Nanchong,Sichuan. According to the history of exposure to Wuhan, the patients were divided into group A (16 cases) with a history of exposure to Wuhan and group B (9 cases) without the previous history. The clinical symptoms and chest CT manifestations of patients in groups A and B were statistically compared. Results Among the 25 patients, there were 12 males and 13 females, aged range from 10 to 77 years. There was no significant difference between the two groups (P＞0.05). 15 patients in group A (93.8%) and 4 patient in group B (44.4%) were presented with clinical symptoms on admission. The clinical symptoms of patients in group A were more early than those in group B, and the difference between groups was statistically significant (P＜0.05). Ground glass opacities and / or consolidation were mainly observed on the initial chest CT images. There was a significant difference in CT image staging between groups A and B (P＜0.05). Conclusion The imported cases with a history of exposure in Wuhan have more obvious clinical manifestations and CT manifestations and a faster process than those with the secondgeneration infection. The secondgeneration cases may show asymptomatic infection and negative chest CT, so nucleic acid test is essential in the diagnosis of suspected cases.