Heparin is an anticoagulant used invariably in all cardiac surgery. Heparin dosing and its reversal were determined by monitoring activated clotting time (ACT). Intermittent heparin dosing after initial bolus dose is widely practiced to maintain ACT level 200-300 seconds in Off-pump coronary artery bypass surgery (OPCAB). Fluctuation of ACT level from this range may cause adverse postoperative outcome. This study was aimed to compare early postoperative outcome between intermittent heparin dose and continuous heparin infusion after initial bolus dose during OPCAB. This comparative cross-sectional study was carried out in National Institute of Cardiovascular Diseases (NICVD), Bangladesh from January 2019 to December 2020. Total 110 patients were enrolled by purposive sampling and divided into 2 groups: Group A where 55 patients received intermittent heparin after initial bolus dose and Group B where 55 patients received continuous heparin infusion after initial bolus dose. Data were analyzed by statistical package for social science (SPSS) version 26.0 and p value <0.05 was considered significant. Baseline ACT level of Group A and Group B was not significant (p=0.800). After bolus dose of Heparin, ACT level of Group A and Group B was not significant (p=0.068). Mean maintenance ACT was 326.34±22.774 seconds in Group A and 258.67±12.285 seconds in Group B patient, which was significant (p<0.001). Peroperatively 29.0% from Group A and 11.0% from Group B developed arrhythmia. Platelet count significantly reduced in Group A (p<0.001). Postoperative mean Troponin I level in Group A was 5.78±1.15 and Group B was 5.32±1.05ng/dl, which is significant (p=0.030). Postoperative blood loss was significantly higher in Group A than Group B (986.36±398.31 vs. 852.73±241.22, p=0.036). There was significantly better reduction of arrhythmia and ischemia in postoperative and on discharge ECG finding in Group B patients (p=0.002). On discharge echocardiography 31.0% from Group A and 13.0% from Group B had regional wall motion abnormality, which is significant (p=0.018). But there was no significant difference in LVEF% (52.65±5.99 vs. 53.85±5.77, p=0.287). Early postoperative outcome of continuous heparin infusion is better than intermittent intravenous heparin after initial bolus dose during Off-pump coronary artery bypass surgery. So, during OPCAB use of continuous heparin infusion after bolus dose is eminent time worthy.