Abstract: Lactose intolerance is a common gastrointestinal disorder. It usually occurs in children. Lactose intolerance is mainly divided into congenital，secondary，primary and developmental according to etiology. Clinical classification is closely related to treatment and prognosis. The severity of the clinical manifestations of lactose intolerance varies greatly among individuals，and is affected by various factors such as lactase expression and activity，and gastrointestinal sensitivity.Severe lactose intolerance can affect the growth of children.Restriction of lactose intake is the main treatment measure，and supplementation of exogenous lactase and β-galactosidase active probiotics can effectively relieve clinical symptoms. The symptoms of most children can be significantly alleviated through dietary adjustment. To avoid nutrient deficiencies，children should be encouraged to limit lactose and dairy products rather than completely avoid them.Children with congenital lactase deficiency need a lifelong lactose-free diet. Most people with lactose intolerance have a good prognosis.

Key words: lactose, lactase, nutrition, child

摘要： 乳糖不耐受是一种常见胃肠道疾病，儿童多见。按病因分型，乳糖不耐受分为先天性、继发性、原发性和发育性，临床分型与治疗、预后密切相关。乳糖不耐受临床表现严重程度个体差异较大，受乳糖酶表达及活性、胃肠道敏感性等多种因素影响，严重乳糖不耐受损害患儿生长发育。饮食干预中限制乳糖摄入是主要治疗措施，应用外源乳糖酶、β-半乳糖苷酶活性益生菌也可有效改善乳糖不耐受症状。大多数患儿通过饮食调整可显著改善症状，为避免营养素缺乏，应鼓励患儿限制而不是完全避免乳糖及乳制品，但先天性乳糖酶缺乏患者需终生免乳糖饮食，大多数乳糖不耐症预后良好。

关键词: 乳糖, 乳糖酶, 营养, 儿童