ObjectiveTo assess the effectiveness of phrenic nerve electrical stimulation (PNES) on extubation outcomes in intensive care unit (ICU) patients undergoing mechanical ventilation using a meta-analysis approach. Methods A comprehensive search was conducted on the Cochrane Library, PubMed, Web of Science, Embase, and China National Knowledge Infrastructure (CNKI) for randomized controlled trials (RCTs) published from database inception to December 2023, evaluating the effect of PNES on extubation outcomes in ICU patients receiving mechanical ventilation. The control group received standard rehabilitation measures, while the intervention group received PNES in addition to standard rehabilitation. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias. Meta-analysis was performed using RevMan5.4 software. Results Nine RCTs were included in the final analysis. The quality assessment indicated that one study was rated as Grade A and eight as Grade B, reflecting relatively high study quality. Meta-analysis results demonstrated that PNES significantly improved extubation success rates [relative risk (RR)=1.33, 95%CI 1.09 - 1.62, P=0.006], maximal inspiratory pressure (MIP) [mean difference (MD)=1.36, 95%CI 0.46 - 2.27, P=0.003], and diaphragmatic thickness fraction (DTF) (MD=7.11, 95%CI 0.53 - 13.69, P=0.03) compared with the control group. PNES also significantly reduced the duration of mechanical ventilation (MD=–2.23, 95%CI –3.07- –1.38, P<0.000 01), re-intubation rates (RR=0.35, 95%CI 0.15 - 0.85, P=0.02), and rapid shallow breathing index (RSBI) (MD=–11.57, 95%CI –18.51 - –4.62, P=0.001). Additionally, PNES shortened ICU length of stay (MD=–4.03, 95%CI –5.95 - –2.11, P<0.000 1), with all differences being statistically significant. Conclusion PNES effectively reduces the duration of mechanical ventilation and ICU length of stay, decreases re-intubation rates and RSBI, and improves extubation success, MIP, and DTF in ICU patients. Future high-quality, large-scale, multi-center RCTs are needed to further validate these findings.