Background: Standard treatment of diaphyseal fractures of the forearm is open reduction and fixation using dynamic compression plates (DCP) and screws. This technique uses screw placement in all 6 or more of the plate holes except the hole over the fracture line. We hypothesized that DCP with selective 4-screw bicortical placement can provide adequate fixation for these fractures. Objectives: The aim of this study was to evaluate the results of conventional 6 or more screw fixation versus 4 screw fixation for adults with diaphyseal fractures of the forearm. Patients and Methods: In this prospective study, 128 fractures of the ulna, radius or both bones of the forearm in 87 patients were treated in either one of these two groups: Open reduction and internal fixation (ORIF) with conventional DCP and screws or ORIF using DCP and selective 4- screw placement. Fractures were transverse or oblique in pattern without gross comminution. In a total of 41 patients with fractures, 28 single ulnar and 18 single radius fractures were included. Follow-up visits were done at 3-6 and 12-16 weeks and at 6 months. Outcome with respect to union an nonunion rates, union time, infection, and device failure was noted. Results: No change in alignment was noted in any patient. Union time in conventional and selective bicortical 4-screw fixation was 74.8 days and 73.6 days respectively which showed no significant difference (P = 0.064). Union rate and infection was 92.1% and 3.2% in conventional and 95.3% and 0% in the selective group respectively. Non-union was observed in 5 and 3 cases of fractures in conventional and the selective group respectively. Conclusions: For treatment of the transverse or oblique diaphyseal fractures of the forearm, fixation by a same length 3.5 mm DCP with selective 4-screw cortical fixation (2 screws on each side of the fracture site) had similar results in comparison with conventional 6 or more DCP screws. Because of lesser impact on host bone and smaller incision, the selective 4-screw insertion can be an alternative technique for treatment of these fractures.