Functional appliances have been used over a century in clinical orthodontic treatments for skeletal Class II malocclusion patients. Its popularity is attributed to its high patient adaptability and ability to produce rapid treatment changes. The twin block and lip bumper can be combined depending on the patient’s cases. The purpose of therapy with twin block is effective in mandibular growth deficiencies to induce supplementary lengthening of mandibular by stimulating increased growth at the condylar cartilage. The patient was a ten-year-old male patient with skeletal Class II malocclusion. He had a convex facial profile, SNA (sella, nasion, A point) angle of 77.5°, SNB (sella, nasion, B point) angle of 73.0°, ANB (A point, nasion, B point) angle of 4.5°, overjet of 6.5 mm, overbite of 11/41 = 5.0 mm, 21/31 = 4.5 mm, abnormal upper labial frenulum, crossbite in the second left premolar of maxilla, crowded anterior teeth of mandibular, deficiency of mandibular growth, lower lip sucking habit, anterior teeth of maxilla with diastema and proclination. Orthodontic treatment for patient is a combination of twin block and lip bumper appliances. After seven months, frenectomy is used to eliminate and correct the spacing in the frenulum. After 10 months, the patient’s skeletal and profile had improved to skeletal Class I malocclusion, SNA angle of 78.0°, SNB angle of 75.0°, ANB angle of 3.0°, overbite and overjet of 4.0 mm, and the lower lip sucking habit had stopped. Twin block and lip bumper appliances are particularly good alternative treatment in managing selected cases of skeletal Class II malocclusion.