Remote ischemic preconditioning (RIPreC) has been regarded as a promising strategy to reduce ischemia-reperfusion injury to the heart and other organs caused by cardiopulmonary bypass. While RIPreC has demonstrated potential benefits in adult cardiac surgery, particularly in reducing postoperative kidney and cardiac dysfunction, evidence in pediatric populations remains limited and inconsistent. This updated systematic review and meta-analysis aims to address these gaps and clarify the efficacy of RIPreC in children undergoing cardiac surgery. A comprehensive search was conducted across PubMed, EMBASE, Cochrane Library, Web of Science, and ClinicalTrials.gov for randomized controlled trials (RCTs) comparing RIPreC with placebo or standard care in pediatric cardiac surgery. Primary outcomes included all-cause mortality, duration of mechanical ventilation, ICU length of stay, aortic cross-clamp time, and postoperative arrhythmia. Meta-analyses were performed using random-effects models to calculate standardized mean differences (SMDs) or risk ratios (RRs), with 95% confidence intervals (CIs). Risk of bias was assessed using the Cochrane RoB 2.0 tool. Fifteen RCTs involving 1570 pediatric patients were included, and 14 were eligible for meta-analysis. RIPreC significantly reduced the duration of mechanical ventilation compared to control (SMD = −0.42; 95% CI −0.79 to −0.06; p = 0.02), although heterogeneity was high (I² = 85.7%). No significant differences were found for ICU length of stay (MD = −0.17 days; 95% CI −0.55 to 0.20), aortic cross-clamp time (MD = 3.22 min; 95% CI −0.52 to 6.97), postoperative arrhythmia (RR = 0.69; 95% CI 0.39 to 1.20), or all-cause mortality (RR = 1.11; 95% CI 0.34 to 3.64).