Objective: To determine the incidence of deep vein thrombosis (DVT) in patients undergoing spinal surgeries receiving prophylactic doses of Deltaparin in a single center in central Iran.Method: This cross-sectional study was conducted in Shariatee hospital of Isfahan during a 12-month period. We included all the patients undergoing elective spinal surgeries in our center during the study period who received prophylactic dosages of subcutaneous Dalteparin (5000 unit daily) the first postoperative day. Those with absolute contraindications of anticoagulation therapy were not included in the study. Patients were followed for 3 months clinically and the incidence of DVT was recorded. DVT was suspected clinically and was confirmed by color Doppler sonography.Results: Overall we included 120 patients with mean age of 44.8 ± 12.6 years among whom there were 54 (45%) men and 66 (55%) women. Lumbar discectomy (32.9%) and laminectomy (20.2%) were the most common performed procedures. DVT was detected in 1 (0.83%) patient in postoperative period. None of the patients developed pulmonary embolism and none hemorrhagic adverse event was recorded. The patient was treated with therapeutic unfractionated heparin and was discharged with warfarin. Conclusion: Our results shows the efficacy of LMWH (Dalteparin) in reducing the incidence of DVT to 0.83%. These results also show the safety of Dalteparin in spine surgery because of lack of bleeding complication.