Objective To investigate the effect of functional exercises at different time and different immobilization positions on the functional recovery of elbow joint with type C distal humeral fractures. Methods A total of 120 patients with type C distal humeral fractures admitted to the hospital between June 2013 and July 2015 were included in the study. They were randomly allocated to 3 groups, 40 patients in each group. Group A: functional exercises began immediately after the operation; Group B: the affected elbow was fixed at 90° flexion for 1 week and then began functional exercises after 1 week of immobilization; Group C: the affected elbow was fixed at 30° extension for 1 week and then began functional exercises after 1 week of immobilization. There was no significant difference in gender, age, fracture pattern, fracture side, injury time, and surgical approach between groups (P>0.05). Results In groups A and B, 1 case had incision redness and swelling respectively, and the other incisions healed by first intention. Five patients occurred myositis ossificans in group A, 4 cases in group B, and 5 cases in group C. The incidence of complications in groups A, B, and C was 15.0% (6/40), 12.5% (5/40), and 12.5% (5/40), respectively. There was no significant difference between groups (χ2=0.144, P=0.930). All patients were followed up 6-25 months, with an average of 9.8 months. At 2 weeks after operation, the Mayo elbow joint function score of group A was significantly higher than those of groups B and C (P<0.05), and the visual analogue scale (VAS) of group A was significantly lower than those of groups B and C (P<0.05). There was no significant difference between groups B and C (P>0.05). At 6 months after operation, there was no significant difference in Mayo elbow joint function score and VAS score between groups (P>0.05). At 2 weeks and 6 months after operation, the flexion and extension activities of elbow joint in groups A and C were better than that in group B (P<0.05), and there was no significant difference between groups A and C (P>0.05). There was no significant difference in forearm rotation between groups (P>0.05). All fractures of 3 groups achieved clinical healing, and there was no significant difference in healing time between groups (P>0.05). Conclusion Early functional exercises can relieve pain and obtain better elbow flexion and extesion activities after operation. The elbow joint fixed at 30° extension is better than at 90° flexion in elbow flexion and extension activitis.