Background: Nonunions with large defect is a problem, especially in large defects with infection this problem is more serious. Due to war and grave accidents in our country, we have encountered with these difficulties and in future time will also. Methods: We modified D.O.B.G by using plate in one side of large defect and metal plate on another side, and fixed these plates using screws anchoring the distal and proximal segments of nonunion sites rigidly. The technique is very simple, reliable, less morbidity in donor site, short operation time and needn's especial instruments and equipments. We use this technique in 146 patients and follow one hundred of thems for 2.5 yrs (mean time) clinically and radiological. Results: Union rate was ninety percent. Due to rigid fixation and early R.O.M of joints the final limbs function were excellent (comparison with others technique). Discussion: Modified D.O.B.G is the choice technique for nonunion with lange defect especially in metaphysis. because of rigid fixation results early R.O.M and good limb function, high union rate, short operation time, simple technique and less morbidity in donor site.