Background: The composite loss of the fascia or tendon and the overlying soft tissue remains a reconstructive challenge. These patients need not only skin coverage but also functional repair. The aim of this paper is to present our approach for varies composite fascia and soft tissue defect using an anterolateral thigh (ALT) flap with a vascularized fascia lata, and functional assessment of the donor and recipient function. Material and Methods: Twelve cases have applied an ALT chemeric flap with vascularized fascia lata for one-staged repair of soft tissue and fascia defects included seven for large abdominal wall defect, four for Achilles tendon and soft tissue defect, one for knee joint and patella ligament defect reconstruction. The age ranged from 29 to 75 year-old with a mean of 45 years. Eight were resulted from trauma; two from cancer origin, and the other two were chronic ulcer origins. The size of ALT flaps ranged from 10 to 32 cm in length and 6 to 18 cm in width, which included a fascia lata graft could be rolled as a vascularized tensor fascia lata graft (8x6 ~ 28x14 cm) to replace the fascia defects. Objective functional assessment of donor and recipient site by using a Cybex-340® isokinetic dynamometer and Kin-Com® communicator machine were performed after more than 1-year follow- up. Results: All 12 flaps were totally survived. Subjectively, four cases for ankle reconstruction cases could resume daily ambulation without any difficulty except mild bulkiness of flap and mild running difficulty. One case for knee joint reconstruction showed the range of motion of knee joint was near fullness except mild weakness of knee extension strength. There were no abdominal herniation was found in all abdominal wall reconstruction (seven cases) except one inguinal incisional hernia after follow-up. All of them satisfied the results except three patients sometimes needed crutch support. Objectively, we evaluated the recipient and donor site function after harvesting the composite ALT flap with fascia lata in six cases. The kinetic communicator machine measurements of plantar and knee flexion strength, power, endurance and range of motion showed mild defect. The quadriceps function of donor thighs showed mild deficiency after dynamometer machine evaluation. Summary: Composite ALT flap with vascularized fascia lata is sufficient to restore adequate contour and fascia function. However, the tension strength using a vascularized fascia lata is still mild insufficient but patients gets acceptable results without obvious ambulating difficulty.