Previous studies have reported discrepant outcomes for mindfulness-based intervention (MBI) to improve sleep quality or reduce the benzodiazepines (BZDs) use in cancer patients; therefore, a meta-analysis was required to examine the relationships. The MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Science, Cochrane Central Register of Controlled Trials et al. were searched by independent reviewers from date of inception to January 2020 to examine the associations between MBI and sleep disturbance or BZDs use among cancer patients. Randomized controlled studies that reported the effect of MBI on sleep disturbance or BZDs use in cancer patients aged over 18 years were included. Standardized mean differences with 95% CIs were calculated to estimate effect size. If P ≥ 0.1, I2 < 50%, the fixed effect model was used for meta-analysis, while if P < 0.1, I2 ≥ 50%, the random effects model was used. Fourteen studies of 1659 participant were identified in the meta-analysis. Overall, sleep disturbance was significantly relieved in MBI group (SMD = 0.37, 95% CI 0.19 to 0.55, P < 0.001), and the effect could sustain to follow up duration (SMD = 0.35, 95% CI 0.02 to 0.69, P < 0.001). Only three studies reported that MBI could decrease the BZDs use in hospitalized cancer patients. Our findings indicate that MBI were effective in alleviating sleep disturbance in a short time, and may be associated with therapeutic benefits for BZDs use. Further randomized controlled studies are needed to examine the effectiveness of MBI for BZDs use in cancer patients.