Many difficult problems are encountered in the treatrnent of infected nonunion of long bone. To solve these difficult fractures, authors adopted an active approach-thorough debridement of the infected and necrotic soft tissue and bone, rigid internal fixation with autogenous cancellous bone graft and opening of the wound to ensure continuous drainage until union of the fracture. Authors treated 28 cases of infected nonunions with this method from Mar. 1980 to Feb. 1989, and the results are as follows ;1. Femur(54%) and tibia(43%) were most frequently involved sites. 2. Most of the cases(86%) were treated by rigid internal fixation and cancellous bone graft. 3. In most cases(64%), infection was controlled spontaneously by the time of bony union, but in 5 cases which showed persistent drainage, implant removal controlled the problem, and residual soft tissue and bony defect were solved by Papineau's technique or musculocutaneous flap. 4. Revision was required in 5 cases(18%) because of insercure fixation. 5. Union could be obtained in average 4.8 months, and infection could be controlled in all except 1 case.