Since December 2019

severe acute respiratory syndrome coronavirus 2（SARS-CoV-2）has spread rapidly

and coronavirus disease 2019（COVID-19）caused by SARS-CoV-2 has become a global pandemic

posing a great threat to human health. As a routine laboratory test

peripheral blood cell parameters are of great significance for the clinical diagnosis and observation of COVID-19

but there is currently a lack of comprehensive reports on the association between peripheral blood cell parameters and COVID-19. This article reviews the value of peripheral blood cell parameters in COVID-19.