PURPOSE In this retrospective, nonrandomized, single-surgeon study, we evaluated the clinical outcomes of dorsal and volar locking plate fixation for AO type C3 dorsally comminuted distal radius fractures. METHODS We treated 41 consecutive patients who had sustained AO C3 dorsally comminuted fractures of the distal radius with 2.4-mm titanium locking plates between 2006 and 2008. Patients in group 1 (n = 22) were treated with dorsal locking plates, and those in group 2 (n = 19) with volar locking plates. We evaluated clinical outcomes at an average of 37 months and performed statistical analysis using the Mann-Whitney U test and Fisher's exact test. RESULTS No significant difference was noted between the 2 groups in terms of radial inclination, volar tilt, and ulnar variance. At the 3- and 6-month follow-up, group 1 showed better clinical results with respect to wrist extension, grip strength, and Gartland and Werley score, whereas group 2 showed better wrist flexion during this period. The range of motion and grip strength progressively leveled out between the 2 groups, and no significant differences were observed at the 9- and 12-month assessments. One patient in group 1 had short-term complex regional pain syndrome, and 4 patients in group 2 had temporary median nerve numbness. CONCLUSIONS Treatment with dorsal or volar locking plates can provide satisfactory radiographic and functional outcomes for AO type C3 dorsal comminuted distal radius fractures. The dorsal plate group showed an earlier recovery of wrist extension, grip strength, and functional score at the 3- and 6-month follow-up owing to direct reduction as well as fragmental-specific fixation of the dorsal fracture fragments. TYPE OF STUDY/LEVEL OF EVIDENCE Therapeutic IV.