Pulmonary hypertension (PH) is a known complication of Gaucher disease (GD) and splenectomy. Although it resembles World Health Organization (WHO) group 1 pulmonary arterial hypertension (PAH), PH due to GD or splenectomy is part of WHO group 5. There are no clinical trials testing therapies in PH due to GD or splenectomy. Several reports suggest that PAH-specific therapies are beneficial in patients with PH due to GD, although data are insufficient to formulate a treatment algorithm for these patients. The tyrosine kinase inhibitor imatinib has been investigated in the treatment of severe PAH, but not in PH WHO group 5. We report a patient with GD and splenectomy who developed PH that progressed while on conventional PAH-specific therapy and improved once imatinib was added to her treatment regimen. This is the first report, to our knowledge, describing significant subjective and objective improvements in response to imatinib in a patient with WHO group 5 PH.