The pathogenesis of tyrosinosis type I is mainly due to reduced or absent fumaryl acetoacetate hydrolase activity, resulting in impaired terminal metabolism of the tyrosine metabolic pathway, with increased fumaryl acetoacetate, its upstream metabolites tyrosine, 4-hydroxyphenylpyruvate, and its bypass metabolites 4-hydroxyphenyllactate and 4-hydroxyphenylacetic acid; increased intermediate metabolites maleoyl acetoacetate and ferredoxin acetoacetate , leading to an increase in its bypass metabolites succinyl acetoacetate, succinylacetone. Succinyl acetoacetate and succinylacetone acid can bind to sulfhydryl groups of proteins and are the main causes of liver and kidney damage [1]. Tyrosinemia type I is clinically classified into acute type (age of onset 2 years) according to the age of onset [3]. The acute type mostly starts in the neonatal period and progresses rapidly with early symptoms similar to neonatal hepatitis, such as vomiting, diarrhea, lethargy, growth retardation, hepatosplenomegaly, edema, jaundice, anemia, decreased PLT, and bleeding symptoms, and often dies of liver failure at 3 to 9 months of age. Late onset usually occurs after 1 year of age and is characterized by growth retardation, progressive cirrhosis and impaired renal tubular function such as hypophosphatasia rickets, glycosuria, proteinuria, and amino aciduria, similar to Fanconi syndrome manifestations [11]. The incidence of liver tumors is high in this disease, with approximately 30% of children having liver tumors, mainly small cell hepatocellular carcinoma, within 3 years of age. About 40% of children have acute peripheral nerve involvement crisis during the course of the disease, which is characterized by irritability, painful sensory abnormalities, hyperextension of the trunk and neck, and autonomic abnormalities such as increased blood pressure, tachycardia, and intestinal paralysis. Most of the untreated children die within l0 years of age. Therefore, early diagnosis and early treatment are the keys to a good prognosis for this disease. Tyrosinemia type I is a treatable genetic metabolic disease, and the main treatments are control of natural protein intake, a phenylalanine-free, tyrosine-formulated nutritional powder diet and nitisinone medication. The aim of the diet is to reduce the intake and production of tyrosine, thereby reducing the level of bypass metabolites and providing a therapeutic effect. The intake of natural protein should be controlled at 1-1.5g/Kg.d, and the dosage of formula nutritional powder without phenylalanine and tyrosine is 1.5-2.0g/Kg.d. However, the controlled diet therapy can only reduce the risk of renal complications, but is not effective for liver disease, and can neither prevent the progression of liver disease nor the occurrence of liver cancer.