Avulsion fractures of the pelvic apophyses among athletes in the adolescent period are rare injuries caused by sudden contraction of the adhesive muscles. Avulsion fracture of the anterior inferior iliac spine (AIIS) in a 15-year-old amateur athlete is presented. The patient's history revealed a sudden pain in the right hip when shooting the ball while playing football on a synthetic field. Pelvic radiograph showed avulsion fracture of the AIIS. The patient was given conservative treatment consisting of an analgesic, anti-inflammatory treatment, and bed rest. The patient, who experienced pain relief following the medical treatment and bed rest for 3 weeks, was mobilised with hip exercises and on crutches. After the detection of union on radiographs taken at the end of the fourth week, he was mobilised with full weight bearing. The patient, who underwent an exercise programme, was allowed to participate in sporting activities at the end of the third month.