High systolic blood pressure (SBP) has been linked to worse cardiovascular outcomes. However, emerging data suggest that in patients with heart failure (HF), low SBP correlates with increased mortality. The purpose was to examine the impact of baseline and post-exercise systolic and diastolic blood pressure (DBP), as well as pulse pressure (PP), on cardiac mortality in patients with systolic HF. One hundred sixty patients with systolic HF (left ventricular ejection fraction 33 ± 8) were studied. Blood pressure (BP) levels were determined at rest and at peak exercise during a cardiopulmonary exercise test. Patients were followed up for a period of 2.5 ± 0.8 years. During this period 22 patients died and 5 subjects underwent heart transplantation. Patients with higher SBP and DBP at rest, and patients with SBP ≥160 mmHg and PP ≥75 mmHg at peak exercise had the most favorable prognosis. There was a fourfold increase in cardiac mortality risk for patients with SBP <160 mmHg at peak exercise (hazard ratio: 3.97, 95% confidence interval: 1.60–9.84) and a threefold increase for patients with PP <75 mmHg at peak exercise (hazard ratio: 2.96, 95% confidence interval: 1.29–6.82). There is an inverse relationship between SBP and cardiac mortality in patients with systolic HF. BP response to exercise could serve as a simple risk stratification model in HF patients.