Background: There are not many reports regarding the treatment approaches of congenital dislocation of the knee in the literature. Therefore, the preferred method of treatment of this rare congenital disease is still controversial. Hereby, we report the treatment outcome of 29 patients admitted in Shafa Yahyaian Hospital during 40 years. Methods: In this retrospective study done in Shafa Yahyaian Hospital in Tehran, Iran during 2010, we retrospectively reviewed the medical records of 29 patients treated conservatively or surgically for congenital dislocation of the knee. Patients had been evaluated for an average follow-up of 8.5 years. Results: Overall, 54 knee dislocations had been treated surgically (58%) or conservatively (42%). Range of knee motion, persistent recurvatum, instability, valgus deformity after treatment and limping were the more important factors reported in the two surgically or conservatively treated groups. Knee function was satisfactory in patients with conservative treatment. Despite 80% of instability in the operated knees, patients could ambulate with or without braces and had a range of motion equal to 80 degrees. Knee function was also good after quadricepsplasty with transarticular pins in selected cases. Conclusion: We recommend a conservative approach to the disease, regardless of the patients age at the time of treatment and subsequent surgery in patients with dissatisfactory recovery. Quadricepsplasty with transarticular fixation is recommended as a good option in treating these patients. Posterior capsulorrhaphy for patients with CDK and ligamentous laxity is also recommended.