To assess whether blood group O patients undergoing left ventricular assist device (LVAD) insertion have higher perioperative transfusion requirements, postoperative chest tube output, and postoperative changes in hematocrit.Retrospective review of 116 LVAD patients from August 2015 to May 2018.Single-institution, urban academic medical center.One hundred sixteen LVAD patients analyzed by blood group: group O (n = 49) versus non-O (n = 67).Transfusions in the combined intraoperative and postoperative period at 7 days and 90 days after LVAD implantation, chest tube output in the first 24 hours, and hematocrit change in the first 48 hours postoperatively.There was no difference between group O and non-O within the univariable analysis for both 7-day and 90-day transfusion rates. Adjusting for covariables, blood type O was not associated with packed red blood cells transfusion after accounting for multiple comparisons (odds ratio 1.33 [1.07-1.66], p = 0.01, where p < 0.005 was considered statistically significant as a Bonferroni correction was performed to control the familywise error rate). Additionally, there was no difference in chest tube output over the first 24 hours (1,129 v 1,057 mL, p = 0.47) or hematocrit change in the first 48 hours postoperatively (3.49 v 4.53%, p = 0.15).O blood group is not a significant predictor of transfusion requirements in the combined intraoperative and postoperative period up to 90 days after LVAD implantation.