Background The objectives of this study were to assess the frequency and severity of pulmonary hypertension (PH) and the effect of sildenafil treatment in patients with recalcitrant pulmonary sarcoidosis. Methods This investigation was a single-center, retrospective study of all patients ( n = 25) with end-stage pulmonary sarcoidosis referred for lung transplantation. Hemodynamic measurements were evaluated by right-side cardiac catheterization in 24 of 25 patients. Sildenafil treatment for patients with sarcoidosis-associated PH was introduced in April 2004. Results The study group of 24 patients (16 men, 8 women) had a median age of 45 (range 35 to 58) years, and duration of sarcoidosis of 11 (range 2 to 38) years. Mean pulmonary arterial pressure (MPAP) was median 36 (range 18 to 73) mm Hg. PH (MPAP >25 mm Hg) was present in 19 of 24 patients (79%). Sildenafil was administered to 12 of 13 patients at a dose of 150 (range 75 to 225) mg/day for 4 (range 1 to 12) months. Sildenafil treatment was associated with reductions in MPAP of −8 mm Hg (CI −1 to −15 mm Hg), and PVR −4.9 Wood units (CI −7.2 to −2.6 Wood units). Cardiac output and cardiac index also increased during treatment ( p = 0.01, respectively). There were no consistent changes in 6-minute walk distance. Conclusions Patients with severe pulmonary sarcoidosis have a high prevalence of PH. Sildenafil treatment was associated with significant improvements in hemodynamic parameters.