Background Treatment of adolescent Blount disease remains challenging. Correction of the deformity in the form of derotation, angulation, and translation is usually required. External fixator is the best fixation method for deformity correction in Blount disease. Methods 27 patients (38 knees) with adolescent Blount disease were divided into 2 groups and underwent either acute correction (19 limbs) or gradual correction (19 limbs). There were no significant differences in patient demographics or preoperative deformity parameters in either group. The external fixator used for acute correction was that described by Khanfour and El-Rosasy, and Ilizarov fixator was used for gradual correction group. Results There was a statistically significant improvement between the preoperative and postoperative parameters of deformity in each group. There was no statistically significant difference between postoperative deformity parameters in either group. Mean fixator time and median operative time were shorter in the acute correction group. Conclusion Both acute and gradual correction of Blount disease with an external fixator produce satisfactory results. The choice of correction method should depend on surgeon preference, patient compliance, and degree of deformity.