Objectives: We investigated the effects of Continuous Positive Airway Pressure (CPAP) on blood pressure (BP) and vigilance in taxi drivers with obstructive sleep apnea (OSA). Methods: Taxi drivers aged ≥60 years were recruited for polysomnography. Those diagnosed with OSA underwent 6 months of CPAP therapy. Baseline and follow-up assessments included 24-hour ambulatory blood pressure monitoring (ABPM) and the psychomotor vigilance test (PVT). Results: Among the 32 participants, 22 (68.8%) were diagnosed with OSA (median age 63.0 [62.0–65.0] years; 21 males). The average CPAP adherence was 3.1±2.3 hours per night, with 23.5% using CPAP for more than 4 hours per night. There were no significant changes in 24-hour mean systolic ABPM (125.9 [116.8–134.9] mmHg to 126.0 [118.3–133.7] mmHg; p=0.93) or reaction times measured by PVT (2.0 [0.0–3.0] lapses to 2.0 [1.0–3.0] lapses; p=0.82) after CPAP therapy. Conclusion: A high prevalence of OSA was observed among taxi drivers. CPAP adherence was suboptimal and did not result in significant improvements in BP or vigilance.