Retrophyllum rospigliosii is a valuable conifer species from the Andean tropical forests, reaching diameters up to 2.5 m and heights of 45 m. Due to its high commercial demand and distinctive shape and size, its wood is highly sought after, leading to its classification as vulnerable on the IUCN Red List. This study evaluated the physical and mechanical properties of R. rospigliosii wood and how these properties vary according to tree diameter and height in plantation-grown specimens in the Cauca department, Colombia. Standard physical and mechanical tests followed international procedures to assess density, dimensional stability, and mechanical performance. The results showed stable wood density, with a basic wood density of 0.35 g/cm³, and a green density of 0.54 g/cm³. Volumetric shrinkage was 3.52% in the radial direction and 5.05% in the tangential direction, indicating good dimensional stability. Mechanical properties included a modulus of rupture (MOR) of 58.23 MPa, a modulus of elasticity (MOE) of 4702.23 MPa in static bending, and a compression strength of 54.08 MPa. Wood properties showed minimal variation across different diameter and height classes, indicating structural uniformity within the plantation. Given these characteristics, R. rospigliosii wood is suitable for non-structural applications such as furniture, moldings, and decorative items. Further studies should explore silvicultural strategies that enhance wood quality while ensuring sustainable management and conservation of this threatened species.