Abstract: Tetrahydrobiopterin is involved in regulating the dynamic balance of many neurotransmitters，hormones and inflammatory factors in the body. It is an important coenzyme in the metabolic pathway of phenylalanine. Tetrahydrobio-pterin deficiency leads to reduced activity of phenylalanine hydroxylase， resulting in neuropsychiatric diseases and hyperphenylalaninemia. The common clinical manifestations of tetrahydrobiopterin deficiency are psychomotor retardation，abnormal muscle tone and convulsions. If there is no timely treatment，the prognosis is poor. This article describes the metabolism of tetrahydrobiopterin and the diagnosis and treatment of tetrahydrobiopterin deficiency，in order to improve knowledge and understanding of the disease，provide reference for clinical diagnosis and treatment，and further improve the outcome of the patients.

Key words: tetrahydrobiopterin（BH4）, metabolism, tetrahyd-robiopterin deficiency, hyperphenylalaninemia

摘要： 四氢生物蝶呤参与调节体内多种神经递质、激素及炎症因子的动态平衡，是苯丙氨酸代谢通路的辅酶，四氢生物蝶呤缺乏导致苯丙氨酸羟化酶活性降低，造成神经精神疾病及高苯丙氨酸血症。四氢生物蝶呤缺乏症的临床表现主要为智力和运动发育迟缓、肌张力异常、抽搐等，如果不及时干预，预后较差。文章主要阐述四氢生物蝶呤代谢及四氢生物蝶呤缺乏症的诊断、治疗，以期提高对该病的认识和理解，为临床诊治提供参考，进一步改善患者预后。

关键词: 四氢生物蝶呤, 代谢, 四氢生物蝶呤缺乏症, 高苯丙氨酸血症