Rubber growing (Hevea brasiliensis) is showing real development in Latin America, where the production of natural rubber is still held back by the incidence of the South American leaf disease caused by a fungus, Microcyclus ulei, recently renamed Pseudocercospora ulei, which causes repeated defoliation of trees. The solutions are genetic in order to grow varieties resistant to the disease, or developing new plantations in areas where disease incidence is less severe and does not present a serious risk due to adverse climatic conditions for the fungus. The aim of this study was to identify areas in Ecuador for their climatic characteristics suitable for rubber growing, and also the zones that are unsuited to the fungus P.ulei, in order to allow the establishment of rubber plantations with less phytosanitary risk. A geographic study was thus carried out at national level based on the biophysical basis of existing data, by selecting the most relevant parameters with their appropriate ranges for rubber cultivation. Different maps were obtained, displaying 749,824 ha suitable for cultivation, of which 80,174 ha are in escape areas.