目的: 探讨儿童青少年抑郁、社交焦虑的现状，并分析儿童青少年脂肪分布与抑郁和社交焦虑的关联。方法: 采取分层整群随机抽样法纳入北京市7~18岁儿童青少年1 412名，使用双能X线吸收法获得其脂肪分布，使用儿童抑郁量表和儿童社交焦虑量表评价其抑郁和社交焦虑情况，采用多元线性回归和限制性立方样条分析估计儿童青少年脂肪分布与其抑郁、社交焦虑的线性与非线性关联。结果: 13.1%和31.1%的儿童青少年分别存在抑郁症状和社交焦虑症状，且男生、低年龄组的抑郁和社交焦虑检出率显著低于女生、高年龄组。儿童青少年的总脂肪率、Android脂肪率、Gynoid脂肪率、Android与Gynoid脂肪比(Android-to-Gynoid fat ratio，AOI)与抑郁和社交焦虑不存在显著性线性关联，但总脂肪率和Gynoid脂肪率与抑郁的非线性关联显著，表现为倒“U”型曲线关系，切点分别为26.8%和30.9%。脂肪分布与抑郁、社交焦虑的关联在不同性别和高低年龄组间差异不存在统计学意义。结论: 儿童青少年的脂肪分布与抑郁和社交焦虑不存在显著性线性关联; 脂肪分布与抑郁呈现倒“U”型曲线，主要表现在总脂肪率和Gynoid脂肪率上，且这种趋势在不同性别和不同年龄组上均表现出一致性。将儿童青少年的脂肪分布维持在一个合适的水平，是未来儿童青少年抑郁、社交焦虑防控关注的方向。

Objective: To investigate the status of depression and social anxiety in children and adolescents, and to analyze the association between body fat distribution and depression, social anxiety in children and adolescents. Methods: A total of 1 412 children aged 7 to 18 years in Beijing were included by stratified cluster random sampling method. Body fat distribution, including total body fat percentage (total BF%), Android BF%, Gynoid BF% and Android-to-Gynoid fat ratio (AOI), were obtained by dual-energy X-ray absorption method. Depression and social anxiety were evaluated by Children Depression Inventory and Social Anxiety Scale for Children. Multivariate linear regression and restricted cubic spline analysis were used to estimate the linear and non-linear correlation between body fat distribution and depression and social anxiety. Results: 13.1% and 31.1% of the children and adolescents had depressive symptoms and social anxiety symptoms respectively, and the detection rate of depression and social anxiety in the boys and young groups was significantly lower than those in the girls and old groups. There was no significant linear correlation between total BF%, Android BF%, Gynoid BF%, AOI and depression and social anxiety in the children and adolescents. However, total BF% and Gynoid BF% had significant nonlinear correlation with depression, showing an inverted U-shaped curve relationship with the tangent points of 26.8% and 30.9%, respectively. In terms of the nonlinear association of total BF%, Android BF%, Gynoid BF% and AOI with depression and social anxiety, the change trends of the boys and girls, low age group and high age group were consistent. The overall anxiety risk HR of body fat distribution in the boys was significantly higher than that in the girls, and the risk HR of depression and social anxiety were significantly higher in the high age group than those in the low age group. Conclusion: There was no significant linear correlation between body fat distribution and depression and social anxiety in children and adolescents. Total BF% and depression showed an inverted U-shaped curve, mainly manifested in Gynoid BF%, and this trend was consistent in different genders and different age groups. Maintaining children and adolescents' body fat distribution at an appropriate level is the future direction of the prevention and control of depression and social anxiety in children and adolescents.