SinceDecember 2019, novelcoronavirus infected pneumonia emerged in Wuhan city and rapidly spread throughout China. In severe novel coronavirus pneumonia cases, the number of platelets, their dynamic changes during the treatment, platelet-to-lymphocyte ratio(PLR)were a concern. We sought to describe platelet feature of these cases.Single-center case series of the 30 hospitalized patients with confirmed Corona Virus Disease(COVID)-19 in Huizhou municipal central hospitalfrom January 2020 to February 2020 were retrospectively analysed. Demographic, clinical, blood routine results, other laborotary results and treatment date were collected and analyzed. Outcomes of severe patients and non-severe patients were compared.Univariate analysis showed that: age, platelet peaks and PLR at peak platelet were the influencing factors in severe patients,multivariate analysis showed that the PLR value at peak platelet during treatment was an independent influencing factor in severe patients.The average hospitalization day of patients with platelet peaks during treatment were longer than those without platelet peaks(P<0.05).The average age of patients with platelet peaks during treatment were older than those without platelet peaks(P<0.05). The patients with significantly elevated platelets during treatment had longer average hospitalization day. And the higher PLR of patients during treatment had longer average hospitalization day.Single-center case series of the 30 hospitalized patients with confirmed COVID-19 in Huizhou municipal central hospital, presumed that the number of platelets and their dynamic changes during the treatment may have suggestion on the severity and prognosis of disease. The patient with markedly elevated platelets and longer average hospitalization day may be related to the cytokine storm. The PLR of patients means the degree of cytokine storm, which might provide a new indicator in the monitoring in patients with COVID-19. This article is protected by copyright. All rights reserved.