Long-acting bronchodilators are the cornerstone of pharmacologic treatment of COPD. The new combination of long-acting muscarinic antagonist (LAMA) tiotropium (TIO) and long acting beta-agonists (LABA) olodaterol (OLO) has been introduced as fist line therapy for COPD. This article analyses the evidence of efficacy and safety of the TIO/OLO combination. A systematic review and metaanalysis of randomized controlled trials (RCT) with a period of treatment of at least 6 weeks, in patients with COPD confirmed by spirometry, comparing combined treatment with TIO/OLO (approved doses only), with any of the mono-components or any other active comparator administered as an inhalator. A total of 10 Randomized controlled trials (RCT) were identified (N = 10,918). TIO/OLO significantly improved trough FEV from baseline to week 12 versus TIO, OLO and LABA/ICS (0.06 L, 0.09 L and between 0.04 and 0.05 L, respectively). TIO/OLO improved transitional dyspnea index (TDI) and St. George's Respiratory Questionnaire (SGRQ) compared with mono-components, with patients more likely to achieve clinically important improvements in TDI (risk ratio [RR]: 1.17, 95% confidence interval [CI]: [1.07, 1.28] versus TIO and RR: 1.14, 95%CI: [1.01, 1.28] versus OLO) and in SGRQ (RR: 1.21, 95%CI: [1.12, 1.30] versus TIO and RR: 1.28, 95%CI: [1.18, 1.40] versus OLO). Patients treated with TIO/OLO showed a significant reduction in the use of rescue medication and no significant differences in frequency of general and serious adverse events were observed between TIO/OLO and mono-components. Treatment with TIO/OLO provided significant improvements in lung function versus mono-components and LABA/ICS with more patients achieving significant improvements in dyspnea and health status. No differences in adverse events were observed compared with other active treatments. PROSPERO register of systematic reviews (). The online version of this article (10.1186/s12931-017-0683-x) contains supplementary material, which is available to authorized users.