Growing skull fracture (GSF) is a rare complication of pediatric head injury. Early diagnosis and immediate surgical intervention are required for the prevention of irreversible brain damage. Surgical management involves water-tight closure of the dural defect and commonly uses autologous materials because of tissue compatibility; however, a large skin flap and craniotomy are necessary to harvest the autologous materials and repair the dural defect. We describe a successful case of endoscopic-assisted duraplasty using collagen matrix in a female infant suffering from early phase GSF. A 4-month-old female infant presented with a GSF. We surgically treated her because the fracture width progressively expanded 6 days post-injury. A zigzag skin incision was made, and the extent of the skull fracture and dural laceration was observed using an endoscope. Utilizing the collagen matrix, duraplasty was performed to completely seal the dural defect. Subsequently, cranioplasty was performed and the opposite sides of the fracture margins were drawn and bonded by nylon suture. Postoperatively, the patient did not develop any complication or experience recurrence. This is the first report of duraplasty using collagen matrix in GSF, and the collagen matrix can be used as a dural substitute. This novel technique was safe and a less invasive surgical approach for treating patients with GSF.