This case report presents a 5-year-old boy diagnosed with juvenile hyaline fibromatosis (JHF), an extremely rare autosomal recessive disorder characterized by the abnormal accumulation of collagen. The patient exhibited a recurrent giant subcutaneous tumor measuring 20 cm in diameter, along with multiple tumors in the oral cavity, gingiva, and joints, leading to significant facial deformity and functional impairments. Previous surgeries at ages 1 and 2 for tumor removal resulted in recurrence. Surgical intervention was performed to excise the large tumor and alleviate symptoms. Pathologic analysis confirmed the diagnosis of JHF. This case highlights the challenges in managing JHF and the need for multidisciplinary approaches in treatment.