The frequency of infected non-union of long bones is increased due to an increment of open fractures, and so its treatment give orthopedic surgeons a rather difficult obstacles. In treatment of twenty two cases of trouble infected non-union that we undergone from march, 1980 to decmber, 1984, we use some principles of treatment, that is, rigid osteosynthesis, autogenous cancellous bone graft and irrigation system, so we obtain the good results. The conclusion are as follows: 1. All cases were men, and they occured more commonly in young adults, 10 cases (45.5%) were in third decade. 2. The fractures of the tibia showed a high frequency of infected non-union, 17 cases (77.3%) were the fractures of the tibia. 3. All cases showed a grave comminution initially, of them 18 cases (81.8%) were open fractures. 4. The most common causative organism of an infection was staphylococcus aureus, 14 cases(63.6%), showed that organism in pus culture. 5. Using the above mentioned principles of treatment, bony union was achieved in 18 cases for average 5 months except 2 cases losting the follow-up and 2 cases undergoing the below knee amputation.