A 10-year-old boy fell from a one-meter-high Jacuzzi ladder in a hot spring facility, landing in a straddle position, and injured his perineum. He visited the emergency room of our hospital immediately after the injury. Magnetic resonance imaging (MRI) revealed a tear of the corpus spongiosum urethra, and compression due to a hematoma. With the hematoma spreading to the scrotum, the testes became inverted and dislocated to the inguinal region on both sides. Without surgery or interventions, the testes descended into the scrotum on the third day after the injury before fibrillation and scarring began. Testicular dislocation by injury is rare and encountered exclusively in children. It is generally treated with surgery to retain testicular function. We selected conservative management, as our patient had a closed injury without testicular torsion, and the testicular dislocation was associated with compression by hematoma, which could possibly recover with regression of the hematoma.