Although several techniques have been described for lower-lip reconstruction, functional reconstruction of total lower-lip defects remains a challenge. This study investigated a functional reconstruction technique for total lower-lip defects. Nine lower-lip defects were reconstructed after cancer ablation using double mental V-Y island advancement flaps, based on mental neurovascular bundle combined with tongue flaps. All flaps survived completely. The patients were followed up for 6 to 20 months. The lip function and sensation were normal, and aesthetic appearance was satisfactory. No patient developed local recurrence or lymphatic metastasis. The technique of combining a double mental neurovascular V-Y island advancement flap with a lingual mucosal membrane flap is ideal for the functional repair of total lower-lip defects after cancer ablation.