: In this study, we measured the activity of coagulation and fibrinolysis and clarified the presence of certain differences between off-pump coronary artery bypass grafting (OPCAB) cases and awake off-pump coronary artery bypass grafting (AOCAB) cases to evaluate whether AOCAB is actually safe from the viewpoint of coagulability. : 8 underwent OPCAB and 6 underwent AOCAB. The following factors inducing coagulation and fibrinolysis were measured for upto 5 days after the operation: platelet counts, prothrombin time, activated partial thromboplastin time, fibrinogen, fibrin degeneration products, d-dimer, thrombin-antithrombin III complex (TAT), α2-plasmin inhibitor-plasmin complex, prothrombin fragment 1, 2 (F1+2), thrombomodulin, β-thromboglobulin (β-TG), and platelet factor-4. : At 5 days after the operation, fibrin degeneration products, d-dimer, α2-plasmin inhibitor-plasmin complex, and F1+2 levels of the OPCAB group were significantly higher compared with their baseline values and those of the AOCAB group. At 5 days after the operation, thrombin-antithrombin III complex levels of the OPCAB group were significantly higher than those of the AOCAB group. Fibrinogen levels of the OPCAB group were significantly higher than their baseline values at 3 days after the operation (POD3) and 5 days after the operation (POD5). : In this study, the hypercoagulable state at POD5 was suggested in the patients in the OPCAB group, but not in those in the AOCAB group. Further study is necessary to confirm these results, and future studies would evaluate the potential benefit of AOCAB procedure from the viewpoint of perioperative coagulability.