The present invention relates to a Hunter syndrome therapeutic agent and, more specifically, to a Hunter syndrome therapeutic agent, which can reduce the number of visits to the hospital by patients with Hunter syndrome to twice a month or less by containing a first composition to be intravenously injected and a second composition to be subcutaneously injected, while exhibiting a medicinal effect equivalent to or greater than that of a conventional once-a-week IV injection, increases drug-taking compliance of patients in comparison to conventional therapeutic agents and treatment methods, and enables enhanced patient welfare and convenience. The IV/SC co-injection method according to the present invention exhibits an equivalent or superior therapeutic effect compared to that of a conventional once-a-week IV injection, while allowing a patient to visit the hospital less frequently than once a week, as in conventional visits, by replacing the conventional once-a-week IV injection method, requiring a patient to visit the hospital once a week, with SC injections by which a predetermined number of times among IV injections can directly be made at home by a guardian of the patient. This runs counter to a conventional concept that the therapeutic effect achieved by an SC injection would not be superior to the therapeutic effect achieved by an IV injection. Therefore, the present invention relates to a therapeutic agent and a treatment method of which an effect of treating Hunter syndrome is dramatically improved over that of a conventional technology.La présente invention concerne un agent thérapeutique de maladie de Hunter et, plus spécifiquement, un agent thérapeutique de maladie de Hunter qui peut réduire le nombre de visites à l'hôpital par des patients atteints de la maladie de Hunter à deux fois par mois ou moins en contenant une première composition à injecter par voie intraveineuse et une seconde composition à injecter par voie sous-cutanée, tout en présentant un e