The invention belongs to the technical field of medicines, and provides a propranolol hydrochloride (PPL.HCL) gel which can be externally used for treating infant superficial hemangioma. The propranolol hydrochloride gel is mainly prepared from propranolol hydrochloride, gel matrix, a percutaneous penetration enhancer, a preservative, a humectant and the like. By using the propranolol hydrochloride gel, adverse reactions such as decreased heart rate, cyanosis, airway hyperresponsiveness, shortage of granular leukocytes, diarrhoea, sleep change and blood sugar reduction caused by orally taking propranolol by hemangioma patients can be reduced and even avoided, and the problems that oral dosage is not easy to control, infants inconveniently take medicines and the like are solved.