CAD accounts for 25% of mortality in Malaysia public hospitals. CABG is one of treatment for patients with CAD, but requires RBC transfusion, which is associated with morbidity and mortality. This study was to evaluate the association between RBC transfusion and morbidity and mortality in CABG patients at the National Heart Centre, Malaysia (IJN). Methods: Retrospective cross-sectional study performed using data from 434 patients who underwent CABG in 2013 and 2014. Subjects had systematic random sampling every fifth subject of the patients in the sequence of dates of the year. Data related to the relationship between RBC transfusion with mortality and morbidity, and the predicting factors captured. Results: 64.3% of CABG patients (n = 279) received RBC transfusion perioperatively. Age, gender, BMI, and EF, were factors that contributed for RBC transfusion. RBC transfusion was a contributor to longer intensive care unit length of stay (ICULOS) and hospital length of stay (HLOS). Multiple logistic regression revealed, for every 1 year increase of age, there is 3.5% higher chance of transfusion. Whereas an increase of 1 kg/m2 of BMI and 1% of EF reduced the odds of RBC transfusion by 13.0% and 3.0% respectively. Conclusions: Age, gender, BMI, and EF determine the probability of needing RBC transfusion during CABG, and RBC transfusion will result in longer ICULOS, and HLOS. Probability of RBC transfusion will be higher in older patients and reduced in those with higher BMI and EF.