Autotransplantation of developing third molars to replace missing posterior teeth in growing patients is now a common procedure and has received increasing attention. The study was carried out to evaluate the clinical and radiographical results of 8 immature third molars autotransplantation. The research subjects consisted of seven patients from 14 to 22 years old (mean age was 19.8), attending the Hanoi Medical University, in whom 8 third molars with different stages of root development were transplanted between March 2009 and July 2011. The postoperative follow-up period varied from 3 to 25 months (mean of 12.7 months). Pulp healing was observed in 7 of 8 teeth, the other transplanted teeth developed pulp necrosis after 2 months. None of transplanted teeth developed replacement resorption or ankylosis, the survival rate was 100 percent. In conclusion, immature third molars autotransplantation is a conservative surgical technique for the replacement of missing posterior teeth and presents favourable prognosis.