BACKGROUND: Behavior and substance addiction is one of the risk factors for deep vein thrombosis (DVT). The aim of this study investigating the relationship between the different clinical manifestations pattern of DVT with the way, the amount and duration of narcotic drugs in patients admitted to St. Alzahra Hospital in Isfahan, Iran, during 10 years. METHODS: In a cross-sectional study we studied all of the patients with DVT in St. Alzahra Hospital since 2003-2013 were studied. FINDINGS: A total of 238 (59.1) of the patients were male and 165 (40.9) female. The mean age of men and women were 18.80 +/- 48 and 19.60 +/- 3.48 years old. The mean length of staying in the hospital was 5.40 +/- 7.20 days. Addiction among patients with DVT was 19.1. 28.2 of men suffered from DVT and 6 of the women were drug addicts (P < 0.001). Among the 77 patients taking the drug, 53.2 were heroin, 35.1opium, and 11.7 used other injectable drugs. The results showed that 19 patients (28.6) were taking the drug once daily, 27.3 twice a day, 6.5 three times a day, 15.6 once a week, and 26 taking the drug twice a week. From 403 patients, 2.2 had a problem in the upper limb, 44.4 in the left hand, and 55.6 in the right hand. The results showed that none of the 77 studied patients had involvement of upper limbs, but all of them in the lower limb. About 11.2 of studied patients were addicted to injective drugs. Also, 6 were addicted to non-injectable drugs and 2 to both injectable and non-injectable drugs. CONCLUSION: DVT has many risk factors and addiction and intravenously (IV) drug abuse one of the most important for this illness and this problem mast be noticed by health worker and physicians