The ABO blood grouping system has been associated with multiple infectious diseases including hepatitis B, rotavirus .... The involvement of ABO blood grouping has also been reported by several studies during the COVID-19 pandemic hence our study related to the investigation of ABO blood group phenotype profile in a series of Tunisian patients affected by COVID-19.The distribution of blood group phenotypes in our COVID-19 patients did not show any significant difference in favor of a particular blood group. The subjects carrying A "A and AB" antigens would have more severe forms with more recourse to resuscitation and longer period of hospitalization.