A total of 12 trials and 718 participants were included. Compared with control, CPAP significantly reduced 24-h systolic blood pressure (SBP) (WMD: - 5.92 mmHg [ - 8.72, - 3.11]; P<0.001), 24-h diastolic blood pressure (DBP) (WMD: - 4.44 mmHg [- 6.26 , - 2.62]; P <0.001), daytime SBP (WMD: - 5.76 mmHg [ - 9.16, - 2.36]; P <0.001), daytime DBP (WMD: - 3.92 mmHg [- 5.55, - 2.30]; nighttime SBP (WMD: - 4.87 mmHg [ - 7.96 , - 1.78]; P = 0.002), and nighttime DBP (WMD: - 2.05 mmHg [- 2.99, - 1.11]; P<0.001) in patients with resistant hypertension and OSA. CPAP improved the blood pressure both in the short (<3 months) and long term (≥ 3 months). No significant impact on mean heart rate was noted (WMD: -2.76 beats per min [- 7.50, 1.97]; P = 0.25). CPAP treatment was associated with BP reduction in patients with resistant hypertension and OSA.