Background and Objectives: Fractures of shaft of humerus consists of 1% -3% of all fractures. Despite the numerous surgical modalities, plate osteosynthesis remains the gold standard for fixation of humerus shaft fractures. The aim of this study is to see the functional results of humerus shaft fractures treated with plating, reemphasizes the effectiveness of plate osteosynthesis in the management of humeral shaft fractures so as to restore the patient structurally and functionally to near normal status. Materials and Methods: This is retrospective and prospective study of 30 cases of fractures of shaft of humerus admitted at S.S.G. Hospital, Vadodara, Gujarat in between july 2015 to june 2016. Cases were sleceted as per inclusion and exclusion criteria. All patients were operated using posterior or anterolateral approach. They were assessed radiologically and clinically for fracture union at regular intervals of 6 wks, 12 wks and 18wks by using DR. R.N. Deweshwar's Score. Results: Our study of 30 cases, there were 25 men and 5 women, with average age of 39 years.16 (53.33%) patients were admitted due to fall from height,12 (40%) due to road traffic accidents and 2 (6.66%) patients due to assult with predominance of right side 20(66.66%) patients. Out of 30 cases 21(70%) patients of middle third, 7 (23.33%) were lower third, and 2 (6.66%) were upper third. 28 patients having close fractures and 2 have open injury. simple transverse fractures were most common that is 12(40%).10 (33.33%) patients were having associate injuries. The fracture united in 29(96.66%) patients with 1 (3.33%) patient going for non-union. Good and full range of shoulder and elbow movements was present in 28 (93.33%) patients with 2 patients having fair shoulder range of movement and 2 patients having fair elbow range of movement. Conclusion: Open reduction internal fixation with plating is an excellent mode of treatment in fracture of shaft of humerus, which consistently gives long term good results.