To evaluate the effects of motor imagery-based brain-computer interface (MI-BCI) training on upper limb function and activities of daily living (ADL) in post-stroke patients through a meta-analysis, providing evidence-based support for clinical rehabilitation practice. Methods: A systematic search was conducted across Chinese and English databases (PubMed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, CBM, VIP, etc.) from their inception to April 2025. Randomized controlled trials (RCTs) investigating MI-BCI for upper limb dysfunction after stroke were included. Two reviewers independently screened literature, extracted data, and assessed methodological quality using the Cochrane Risk of Bias Tool and PEDro scale. Meta-analysis was performed with RevMan 5.4 software, using standardized mean difference (SMD) and 95% confidence intervals (CI) as effect measures. The Fugl-Meyer Assessment for Upper Extremity (FMA-UE) and modified Barthel Index (MBI) were synthesized, supplemented by subgroup analysis and publication bias assessment. Results: Fourteen RCTs were included. Meta-analysis revealed that MI-BCI significantly improved upper limb motor function compared to controls, as reflected by FMA-UE scores (SMD=0.59, 95% CI: 0.42～0.76, P<0.001), and enhanced ADL performance indicated by MBI scores (SMD= 0.80, 95% CI: 0.57～1.02, P<0.001). Subgroup analyses demonstrated more pronounced improvements in both outcomes when treatment duration ≤30 minutes or intervention period ≤ 4 weeks (all P<0.001). The overall quality of included studies was favorable, with no significant publication bias detected. Conclusion: MI-BCI training effectively enhances upper limb function and ADL in stroke survivors, particularly with shorter sessions (≤30 minutes) and brief intervention cycles (≤4 weeks). Future research should prioritize high-quality, long-term follow-up studies to validate its sustained efficacy and optimize therapeutic protocols.