Background: Glutathione S-transferase (GST) is known as detoxifying enzyme, especially associated with smoking. Recent studies reported the relation of GST polymorphism and diseases, that null genotypes of GSTM1, GSTT1 increase malignancies, respiratory diseases, coronary artery diseases. Our hypothesis was that polymorphic GSTM1 & GSTT1 genes modulate the risk of variant angina in association with smoking. Methods: We investigated 36 variant angina patients who had positive intravenous ergonovine test by coronary angiography and control 29 subjects who had negative intravenous ergonovine test. GSTM1 and GSTT1 genotypes were analyzed by PCR. Results: There was no significant difference between variant angina patients and normal control in GST polymorphism distribution. In consideration of smoking, there was no difference either. Conclusion: Our observation did not show the association with GST polymorphism and variant angina-smoking. Taking consideration into the fact that there was no study about GST and coronary artery disease, variant angina in Korea, further study would be required.