Objective: To determine the frequency of heart failure in non ST-elevation myocardial infraction (NSTEMI) patients presenting in Faisalabad Institute of Cardiology. Study Design: Descriptive, Cross Sectional study. Setting: Cardiac Emergency, Faisalabad Institute of Cardiology, Faisalabad. Period: July 2019 to January 2020. Results: A total of 150 patients between 18 to 75 years of either gender admitted with NSTEMI were included. Patients with active cancer or any malignant tumor or autoimmune inflammatory disease, other than NSTEMI, such as STEMI, unstable angina, takotsubo cardiomyopathy and myocarditis, liver and renal failure were excluded. Each patient was assessed by history taking and clinical examination to ensure the diagnosis of heart failure. Smoking, hypertension, dyslipidemia, diabetic, previous history of MI, CABG and pPCI were noted. Age range in this study was from 18 to 75 years with mean age of 44.28 ± 7.70 years. Majority of the patients 88 (58.67%) were between 18 to 45 years of age. Out of the 150 patients, 116 (77.33%) were male and 34 (22.67%) were females with ratio of 3.4:1. Frequency of heart failure in non-ST elevation myocardial infraction (NSTEMI) patients was found in 20 (13.33%) patients. Conclusion: This study concluded that there is high frequency of heart failure in non-ST elevation myocardial infraction (NSTEMI) patients.