The objective of this study was to determine the natural durability of the sapwood and heartwood of Ponderosa pine from the Aysén Region exposed to 4 types of wood-decay fungi; 2 of them resulting in brown-rot and 2 on white-rot. The results obtained allowed to assign natural durability categories according to Findlay's and ASTM D2017 scales. The methodology was based on the block-soil test described in the American standard AWPA E10-01. The results from heartwood showed that brown-rot fungi were the most aggressive compared to white rot, allowing Ponderosa pine wood to be characterized as Non-Durable, condition by which this wood requires a preservation treatment for structural applications, accordingly indicated by the General Ordinance of Urban planning and Construction of Chile.