Purpose: To observe the pre- and postoperative three-dimensional (3D) nasal morphologies following mandibular ramus cortical bone augmentation (CBA) for a concaved nasal dorsum in definitive correction of an underdeveloped unilateral cleft lip (UCL) nose. Subjects and Methods: Three Japanese women with complete unilateral cleft lip and palate (UCLP) underwent nose correction using CBA on the flat or concaved nasal dorsum in combination with an extended spreader cartilage graft. The measurement items included the nasal dorsal angle, the nasal tip angle, and the x- and z- axis values of the nasal dorsum ridge and nasal tip points. The results were compared with those of thirteen sex- and age-matched women with complete UCLP who underwent the same nasal correction excluding CBA. Postoperative changes in cortical bone were also observed radiographically. Results: The nasal dorsal angle increased and nasal tip angle decreased postoperatively in the patients with CBA, becoming more similar to those of subjects without CBA. Postoperatively, improvement of the lateral nose profile with natural hardness was achieved in three all patients with CBA. 3D analyses of patients with CBA demonstrated an increased height of the nasal dorsum ridge and nasal tip points in the center of the face. Radiological observation revealed remaining transplanted cortical bone, although it became smaller. Conclusions: Mandibular ramus cortical bone augmentation may be one of the options for molding up the severely concaved nasal dorsum on definitive correction of an underdeveloped nose in Asian patients with complete UCLP, without damaging other parts of the body.