Objective: Cardiological evaluation before transplantation is extremely important in predicting cardiac complications in hematopoietic stem cell transplantation (HSCT) patients. In this study, our aim is to determine the incidence of post-HSCT early cardiac complications’ mortality and morbidity and to identify the risk factors which act on the development of cardiac complications. Material and Methods: This study included 218 patients who had undergone HSCT during the time period between January 2014 and January 2020. Patient data were retrospectively retrieved from patient charts and internal electronic record database. Results: Fifty six % (n=122) were males and median age of the cohort was 55 (47-63) years. Eight (3.6%) patients developed Grade III-IV cardiac complications. Patients with ST-T alterations in the pre-transplant electrocardiogram (ECG) had a higher rate of cardiac complications (chi-square, p=0.019). Among the conditioning regimens, cardiac toxicity was determined at a higher rate the group who received melphalan 200 mg/m2(p=0.040). Conclusion: ST segment and T-wave alterations observed in ECG, pulmonary arterial pressure as measured by electrocardiography and particularly a reading over ˃25 mmHg, utilization of melpahalan 200 mg/m2as conditioning regimen feature out as the most important risk factors for cardiac complications which may develop subsequent to HSCT.