To identify the prevalence of mental health problems and sleep disturbances among nursing students during the COVID-19 pandemic. Background: As a future professional workforce, nursing students are expected to play a role in controlling the COVID-19 pandemic; however, physical and mental health problems may hinder their willingness to stay in the nursing profession. Evidence of the prevalence of the health problems among nursing students related to COVID-19 may allow educators to manage their students' health problems and make them feel more positive about their future careers. Design: Systematic review and meta-analysis. This study was prospectively registered with PROSPERO. Data sources: Databases, including CINAHL, Embase, PubMed and Web of Science, were searched for all related journal articles, from database inception to June 29, 2021, published between 2020 and 2021. Methods: This review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines using a PICOS search strategy. A DerSimonian-Laird random-effects model was used to estimate the prevalence and potential heterogeneity among the selected studies using the Cochran Q statistic and I-square test. Publication bias was assessed using the Egger intercept test. Results: Seventeen studies were included in the meta-analysis, representing 13,247 nursing students. During the COVID-19 pandemic, the prevalence of four health problems and sleep disturbances were identified. The health problem with the highest prevalence in nursing students was depression (52%). Other COVID-19-related health problems were fear (41%), anxiety (32%) and stress (30%) and sleep disturbances (27%). Conclusions: The findings from this study showed that strategies are necessary to manage nursing students' teaching and learning during the COVID-19 pandemic or similar future situations. Our results suggest that preparing modified distance learning might reduce the prevalence of health problems related to the educational process. In addition, providing regular mental health assessments or online mental health services to students may improve their mental health and increase their well-being. Nursing education policies regarding clinical practice remain to be formulated to ensure the achievement of competencies to support future careers while considering the mental readiness and safety of students.