Background: Supplemental oxygen administration by apnoeic oxygenation during laryngoscopy for tracheal intubation is intended to prolong safe apnoea time, reduce the risk of hypoxaemia, and increase the success rate of first-attempt tracheal intubation under general anaesthesia. This systematic review examined the efficacy and effectiveness of apnoeic oxygenation during tracheal intubation in children. Methods: This systematic review and meta-analysis included randomised controlled trials and non-randomised studies in paediatric patients requiring tracheal intubation, evaluating apnoeic oxygenation by any method compared with patients without apnoeic oxygenation. Searched databases were MEDLINE, Embase, Cochrane Library, CINAHL, ClinicalTrials.gov, International Clinical Trials Registry Platform (ICTRP), Scopus, and Web of Science from inception to March 22, 2023. Data extraction and risk of bias assessment followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) recommendation. Results: After initial selection of 40 708 articles, 15 studies summarising 9802 children were included (10 randomised controlled trials, four pre-post studies, one prospective observational study) published between 1988 and 2023. Eight randomised controlled trials were included for meta-analysis (n=1070 children; 803 from operating theatres, 267 from neonatal intensive care units). Apnoeic oxygenation increased intubation first-pass success with no physiological instability (risk ratio [RR] 1.27, 95% confidence interval [CI] 1.03–1.57, P=0.04, I²=0), higher oxygen saturation during intubation (mean difference 3.6%, 95% CI 0.8–6.5%, P=0.02, I²=63%), and decreased incidence of hypoxaemia (RR 0.24, 95% CI 0.17–0.33, P<0.01, I²=51%) compared with no supplementary oxygen administration. Conclusion: This systematic review with meta-analysis confirms that apnoeic oxygenation during tracheal intubation of children significantly increases first-pass intubation success rate. Furthermore, apnoeic oxygenation enables stable physiological conditions by maintaining oxygen saturation within the normal range. Clinical trial registration: Protocol registered prospectively on PROSPERO (registration number: CRD42022369000) on December 2, 2022.