Introduction: Obstructive sleep apnea (OSA) is a neglected and underdiagnosed disease in rural and suburban India. Chronic obstructive pulmonary disease (COPD) associated with OSA is termed overlap syndrome. OSA and COPD both cause pulmonary hypertension (PH) that further aggravates nocturnal hypoxia. Aim and objective: To estimate the prevalence of PH in OSA and overlap syndrome. Materials and methods: Patients coming to our outpatient department with symptoms of OSA were selected by STOP-BANG criteria for polysomnography (PSG). One hundred patients with apnea–hypopnea index (AHI ≥5) with symptoms and AHI ≥15 without symptoms were taken for pulmonary function test (PFT) and chest X-ray to rule out COPD. Thereafter, 2D echocardiography (2D-echo) was done to check cardiac changes and the assessment of pulmonary artery pressure. Results: Out of 100 patients in the study group, 10% (n = 10) had mild, 12% (n = 12) had moderate, and 78% (n = 78) had severe OSA. Overlap syndrome was present in 60% (n = 60) of the patients. PH was present in 24% (n = 24) of cases--mild (n = 10) and moderate (n = 10) PH each was 10%, and severe (n = 4) PH was present in 4% of the cases. PH was present in 36.67% (n = 22) of the patients with overlap syndrome and only 5% (n = 2) of the patients with OSA. Conclusions: Nearly, one-fourth of the patients with OSA and overlap syndrome have PH. Prevalence of PH is seven times higher in overlap syndrome than in OSA alone.