Background: Association between pulmonary hypertension and left ventricular diastolic dysfunction in hypertensive patients has been observed. However, the relation between the severity of pulmonary hypertension and different indices of diastolic dysfunction is still unclear. Objectives: To explore the relationship between pulmonary hypertension severity and different indices of LV diastolic dysfunction in hypertensive patients. Patients and methods: 112 asymptomatic hypertensive patients were included in our study. History taking, clinical examination, and echocardiography were done to all patients, LV dimensions, systolic and diastolic function, and systolic pulmonary artery pressure (SPAP) were measured. We classified the patients into two groups according to the presence or absence of diastolic dysfunction. Results: Patients with diastolic dysfunction had significantly higher SPAP (p < 0.00001), and significantly higher incidence of severe pulmonary hypertension (p = 0.034). There was a significant positive correlation between SPAP and E/E0 ratio (r = 0.354, p = 0.00013), and between SPAP and systolic blood pressure (r = 0.231, p = 0.231), and a significant negative correlation between SPAP and E0/A0 ratio (r = 0.289, p = 0.0019), and between SPAP and E-wave DT (r = 0.265, p = 0.0047). Independent predictors for the presence of severe pulmonary hypertension were E/E0 > 15, E0/A0 < 1, and E-wave DT < 160. Conclusion: Hypertensive patients with diastolic dysfunction had a higher systolic pulmonary artery pressure and a higher incidence of severe pulmonary hypertension. Systolic pulmonary artery pressure was significantly correlated with of LV diastolic dysfunction indices.