Rationale: Pediatric pyloric obstruction is a condition characterized by complete or incomplete obstruction of the distal stomach caused by obstructive lesions of the distal stomach, pyloric duct, or proximal duodenum. Congenital hypertrophic pyloric stenosis is the most common cause of pediatric pyloric obstruction, whereas acquired pyloric stenosis is comparatively rare, with peptic ulcer disease being the most common cause. Patient concerns: We describe a case of a 5-year-old girl who had peptic ulcer disease and developed scarring pyloric stenosis. We also give comprehensive details of the diagnosis and course of treatment. Diagnosis: Intraoperative findings revealed ulcerative, scarring pyloric obstruction. Interventions: Conservative treatment failed and surgery was subsequently performed. Outcomes: No further vomiting symptoms occurred after surgery. And 3 months after surgery, the patient had gained weight on average and had no further complaints. Lessons: Although scarring pediatric pyloric blockage due to peptic ulcer is less common, emphasis should be placed on rapid diagnosis by accurate gastroscopy, barium meal of the gastrointestinal tract, or ultrasonography. Depending on the patient’s condition, conservative treatment or surgery should be chosen carefully selected.