Objective <p>This meta-analysis aimed to evaluate the relationship between borderline personality disorder symptoms, and mindfulness.</p> Method <p>We identified 20 eligible studies (<i>n</i> = 5736) that we included in the meta-analysis. We hypothesized a negative association between borderline personality disorder symptoms and mindfulness, with potential moderation by participant and study characteristics. We used meta-analytic techniques.</p> Results <p>The results indicate a negative relationship between borderline personality disorder symptoms and mindfulness (<i>r</i> = -0.32, 95% CI [-0.38, -0.26]). The association was stronger in studies using the total score of borderline personality disorder symptoms (<i>r</i> = -0.38, 95% CI [-0.46, -0.30]) compared to the studies assessing individual subscales. Non-judging (r = -0.46) and acting with awareness (<i>r</i> = -0.35) showed the strongest negative associations, while observing showed a positive association (<i>r</i> = 0.11). The relation is also stronger in studies using European samples (<i>r</i> = -0.51) and in those using The Mindful Attention Awareness Scale (<i>r</i> = -0.45).</p> Conclusions <p>The negative relationship between borderline personality disorder symptoms and mindfulness across clinical and non-clinical samples suggests that mindfulness-based interventions could be beneficial for prevention programs in at-risk populations. Furthermore, the stronger relationships observed with non-judgment and acting with awareness suggest that clinical interventions could benefit from specifically emphasizing these components.</p> Preregistration <p>This study was preregistered in PROSPERO (CRD42024558067).</p>