Nitric oxide (NO) is involved in different stages of malignancies. Increased levels of NO have been reported in different leukemias. Imatinib is the preferred drug for the treatment of chronic myeloid leukemia (CML). Turmeric powder contains curcumin which has anti-leukemic property and also decreases NO synthesis. This study was conducted on fifty patients of CML divided into two groups, group A receiving imatinib alone and group B receiving turmeric powder along with imatinib for six weeks. Nitric oxide levels were estimated in these patients before and after receiving therapy and were analyzed statistically. Nitric oxide levels were found to be significantly decreased in both the groups, but more significantly in group B after receiving the respective treatments. Thus, curcumin acts as an adjuvant to imatinib in decreasing the NO levels and may help in the treatment of CML patients.