Introduction: Infected nonunion of the distal humerus is a challenging condition to treat, and Ilizarov treatment may be a viable option in some cases. Ilizarov treatment involves the use of an external fixation device to stabilize the bone and promote bone healing. Aim of the Study: The aim of this study was to evaluate the function of infected nonunion of the distal humerus using Ilizarov treatment. Methods: This prospective study was conducted in Department of Orthopedics, Dhaka Medical College Hospital, Dhaka, Bangladesh, during the period from June 2003 to June 2007. Total 203 patients with infected nonunion of the distal humerus were included in this study. Result: In our study, mean age of the sample is 41.9 (SD±16.31) years. Majority of the study subject (58.6%) were female. The mean value of time to union was 8.1 months, with a standard deviation of 2.34 months. Mean follow up period was 35.5 months, with a standard deviation of 15.7 months. In bone results, majority of the study subject (63.1%) had an excellent outcome. In the functional results, most of the study subject (69.5%) had an excellent outcome. Regarding complications, majority of the study population (41.4%) had pin tract infection. For the elbow ROM arc parameter, there is a statistically significant difference between the preoperative and postoperative values (P=0.0016). The mean shoulder abduction reduced from 128.02° (SD±32.56°) to 123.75° (SD±24.25°) after treatment. For the shoulder abduction parameter, there is no statistically significant difference between the preoperative and postoperative values (P=0.1348). The DASH score decreased from a mean of 31.14 to 9.61 after treatment. For the DASH score, there is a highly statistically significant difference between the preoperative and postoperative values (P<0.0001). The mean preoperative VAS score was 7.05. After completion of treatment, the mean VAS score dropped to 2.21. For VAS score, there is a highly statistically significant .......