ObjectiveTo investigate the epidemiological characteristics of the first cluster of patients with coronavirus diseases 2019 (COVID-19) in Gansu.MethodsAll 6 COVID-19 patients from a non-familial cluster in Gansu, were extracted from Gansu Provincial Health Information System until Feb 20, 2020. The patients were confirmed by nucleic acid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The analyses were included via retrospective method: patient clinical characteristics, the summary of epidemiology, and CT image characteristics.ResultsThis clustered outbreak was the first non-family clustered outbreak in Gansu after traveled to Thailand. All 6 COVID-19 confirmed patients were a kindergarten staff in Gansu, aged from 26 to 51 years, and were female. They traveled to Thailand in the same period, and had the same epidemiological exposure history. They were diagnosed as COVID-19 by transnasopharyngeal swab real-time fluorescent reverse transcription-PCR for SARS-CoV-2 nucleic acid examination at different time points after return to Gansu. The first patient was ill on January 21, 2020, with fever as first symptom. She was diagnosed at the Xigu District People’s Hospital in Lanzhou and was transferred to Lanzhou Pulmonary Hospital after being diagnosed. She was cured with one week’s antiviral treatment. The remaining 5 patients were treated in Longxi People’s Hospital. The common clinical symptoms were fever, throat discomfort, headache, and fatigue. Through 7 to 10 days’ antiviral treatment, they all were cured. All patients belonged to common type and had good prognosis.ConclusionThe COVID-19 patients in a non-familial cluster have the same epidemiological history. Early medical observation, SARS-CoV-2 nucleic acid examination and comprehensive chest CT should be arranged promptly to make diagnosis and give responsive treatment, so that the prognosis is often good.