Background: There are few reports of electrocardiogram (ECG) findings and their prognostic value in acutely ill patients admitted to low resource hospitals in sub-Saharan Africa. Methods: We undertook an observational study of acutely ill medical patients admitted to a low-resource hospital in Uganda. Vital signs were used to calculate the National Early Warning Score (NEWS), and all ECGs were assessed using Tan et al.’s scoring system as described in Clin Cardiol 2009;32:82–86. Results: There were 1361 ECGs performed, covering 68% of all acutely ill medical patients admitted to the hospital during the study. The most common ECG abnormality was a prolonged QTc interval (42% of all patients) and left ventricular hypertrophy (13.5%). Compared to the 519 patients (38%) with no Tan score abnormality, the 842 (62%) patients with one or more abnormalities were more likely to die in hospital (OR = 2.82; CI95% = 1.50–5.36) and within 30 days of discharge (OR = 2.46; CI95% = 1.50–4.08). There was no relationship between age and mortality; however, after adjustment by logistic regression, any NEWS ≥1 on admission, a Tan score of ≥1, and male sex all remained clinically significant predictors of both in-hospital and 30-day mortality. Discussion: The majority of acutely ill medical patients admitted in a low-resource hospital in sub-Saharan Africa had ECG abnormalities, of which prolonged QTc and left ventricular hypertrophy were most common. Those with any Tan score abnormality were twice as likely to die as those without an abnormality.