The six-minute walk test is a sub-maximal exercise test that measures the exercise capacity in patients with pulmonary hy- pertension (PAH). It’s easy, useful as a prognostic indicator and allows monitoring the effectiveness of specific treatments and monitor the natural course of the disease. Objective: To study the exercise capacity of all etiologies of PAH through the six-minute walk test and the changes and potential effects of drugs after 4 to 6 months. Measures: heart rate, O2 satu- ration, blood pressure, end of the test and motive, specific treatments before and during the study, functional class New York Heart Association (NYHA) and mortality. Results: 58 participants, 6 (10.3%) died. 38 patients (65.5%) performed the first test, 34 (58.6%) the second test and 29 (50%) both, of them 14 (48.2%) improved in distance walked. The average dis- tance traveled in the first test was 386.6 +128.1 meters (m) and the second 418.6 +103.1 m. This was higher in men in both tests (p=0.049, p=0.006). The number of patients in NYHA functional class III and IV was significantly lower in the second interview (p=0.003) and improvement in functional class NHA was associated with greater distances covered in the second test (p=0.002). Just the beginning of Sildenafil during the follow-up showed an improvement in the distance (p=0.023). The desaturations >10% in the first test were more frequent among patients who died (p=0.032). No etiology of PAH walked a significantly shorter distance.