Objective: There is little information on the incidence and prognostic significance of hypertension in ST segment elevation myocardial infarction (STEMI) patients, especially in Bangladeshi population. The study aimed to compare the demographic & clinical characteristics and in-hospital outcome of hypertensive versus non-hypertensive patients with STEMI. Design and method: This prospective observational study was conducted from January 2015 to December 2022 at National Heart Foundation Hospital & Research Institute. Patients were divided into two groups: hypertensive and non-hypertensive groups. Results: A total of 10378 patients were enrolled in this study. Of them 65.6% (6813) patients were hypertensive, and 34.4% (3565) patients were non-hypertensive. Mean age of the hypertensive group was 55.89 ± 11.18 years and the non-hypertensive group was 53.49 ± 12.25 years (p = 0.001). In hypertensive group, 84.1% patients were male and 15.9% were female & in non-hypertensive group, 90.4% patients were male and 9.6% were female (p = 0.001). Compared to non-hypertensive patients, hypertensive patients were predominantly non-smoker (49.1% vs 39.9%; p = 0.001), diabetic (68.3% vs 32.1%; p = 0.001), dyslipidemic (80.7% vs 77.3%; p = 0.001), obese (37.8% vs 32%; p = 0.001), have positive family history of ischemic heart disease (IHD) (29% vs 22.4%; p = 0.001), prior history of percutaneous coronary angioplasty (3.7% vs 2.1%; p = 0.001), prior history of myocardial infarction (5.8% vs 4.6%; p = 0.007), and chronic kidney disease (48.2% vs 40.2%; p = 0.001). Hypertensive patients had more multi-vessel disease (49.3% vs 42.6%; p = 0.001), higher in-hospital complications (acute left ventricular failure-24.4% vs 21.9%; p = 0.005) and in-hospital death (4.8% vs 4%; 0.04). Conclusions: Hypertensive patients with STEMI were predominantly non-smoker, diabetic, dyslipidemic, obese, have positive family history of IHD, chronic kidney disease and had higher in-hospital complications & in-hospital death.