COVID-19 was declared a pandemic in March 2020, resulting in many countries worldwide calling for lockdowns. This study aimed to review the existing literature on the effects of the lockdown measures established as a response to the COVID-19 pandemic on the mental health of children and adolescents. Embase, Ovid, Global Health, PsycINFO, Web of Science, and pre-print databases were searched in this PRISMA-compliant systematic review (PROSPERO: CRD42021225604). We included individual studies reporting on a wide range of mental health outcomes, including risk and protective factors, conducted in children and adolescents (aged ≤ 19 years), exposed to COVID-19 lockdown. Data extraction and quality appraisal were conducted by independent researchers, and results were synthesised by core themes. 61 articles with 54,999 children and adolescents were included (mean age = 11.3 years, 49.7% female). Anxiety symptoms and depression symptoms were common in the included studies and ranged 1.8–49.5% and 2.2–63.8%, respectively. Irritability (range = 16.7–73.2%) and anger (range = 30.0–51.3%), were also frequently reported by children and adolescents. Special needs and the presence of mental disorders before the lockdown, alongside excessive media exposure, were significant risk factors for anxiety. Parent–child communication was protective for anxiety and depression. The COVID-19 lockdown has resulted in psychological distress and highlighted vulnerable groups such as those with previous or current mental health difficulties. Supporting the mental health needs of children and adolescents at risk is key. Clinical guidelines to alleviate the negative effects of COVID-19 lockdown and public health strategies to support this population need to be developed.

2020 年 3 月，COVID-19 被宣布为大流行病，导致全球许多国家呼吁实行封锁。本研究旨在回顾现有文献，探讨为应对 COVID-19 大流行而采取的封锁措施对儿童和青少年心理健康的影响。在此符合 PRISMA 标准的系统评价中检索了 Embase、Ovid、Global Health、PsycINFO、Web of Science 和预印本数据库（PROSPERO：CRD42021225604）。我们纳入了针对暴露于 COVID-19 封锁的儿童和青少年（年龄 ≤ 19 岁）进行的针对各种心理健康结果的个别研究，包括风险和保护因素。数据提取和质量评估由独立研究人员进行，并按核心主题综合结果。纳入 61 篇文章，涉及 54,999 名儿童和青少年（平均年龄 = 11.3 岁，49.7% 为女性）。焦虑症状和抑郁症状在纳入的研究中很常见，分别为 1.8-49.5% 和 2.2-63.8%。儿童和青少年也经常报告烦躁（范围 = 16.7–73.2%）和愤怒（范围 = 30.0–51.3%）。封锁前的特殊需求和精神障碍，以及过度的媒体曝光，是焦虑的重要危险因素。亲子沟通对焦虑和抑郁有保护作用。 COVID-19 封锁导致了心理困扰，并凸显了弱势群体，例如那些以前或现在有心理健康问题的人。支持高危儿童和青少年的心理健康需求是关键。需要制定减轻 COVID-19 封锁负面影响的临床指南和支持这一人群的公共卫生策略。