Objective To use thromboelastograph (TEG) technique for examining the platelet inhibition effect by aspirin and clopidogrel before percutaneous transluminal angioplasty and stenting (PTAS), so as to search for the optimal timing, dosage for clinical practice. Methods The clinical data of 93 patients were divided into 4 groups according to the aspirin history and different doses of aspirin before PTAS; the 4 groups were: non-medication history with aspirin+lower dose aspirin (aspirin 100 mg+clopidogrel 75 mg, Group 1), non-medication history with aspirin+higher dose aspirin(aspirin 300 mg+clopidogrel 75 mg, Group 2), medication history with aspirin+lower dose aspirin(Group 3), and medication history with aspirin+higher dose aspirin(Group 4). The blood samples were collected on day 1, 3 after anti-platelet aggregation drugs; TEG technique was used to detect arachidonic acid (AA)-induced inhibition rate of platelet aggregation and adenosine diphosphate (ADP) receptor-induced inhibition rate of platelet aggregation. Results For different time points: in group 1, the inhibition rates of platelet aggregation of aspirin and clopidogrel were significantly higher on day 3 (AA: \[89.09±17.42\]%, ADP: \[57.02±23.97\]%) as compared with those on day 1 (AA: \[ 82.24±22.25\]%, ADP: \[49.62±25.44\]%; P<0.05); in group 3, the inhibition rates of platelet aggregation were also significantly higher on day 3 (AA: \[95.06±8.05\]%, ADP: \[47.76±24.95\]%) than those on day 1 (AA: \[88.88±14.66\]%, ADP: \[36.17±22.71)%\]%; P<0.05). For different doses: the AA-induced inhibition rates were not significantly different between group 1 and group 2 or between group 3 and group 4 on day 1 and 3. Conclusion Without aspirin history, the inhibitory effect of platelet aggregation of aspirin before PTAS for 3 d is better than that for 1 d, and there is no difference between those of lower and higher doses.