To evaluate the inheritance of natural durability of Acacia mangium Willd., wood-color parameters (Y [lightness], x [red to green], and y [yellow to blue]), mass loss by a white-rot fungus (Trametes versicolor) and brown-rot fungus (Fomitopsis palustris), and three different extracts (methanol extract, total phenol, and total flavanol content) were measured using the inner and outer heartwood of 10-year-old trees from 20 half-sib families in the third-generation A. mangium in Indonesia. The broad-sense heritability (H
2) values were moderate to high for the wood-color parameters and mass loss by white- and brown-rot fungi (H
2 = 0.210–0.851) and low to moderate for three different extracts (H
2 = 0.000–0.576). Significant negative phenotypic correlations were found between the three different extracts and mass loss by T. versicolor and F. palustris. In addition, negative correlations were found between the wood-color parameters and three different extracts. Similar results were found between the total phenol content and y and between the total flavanol content and Y in genetic correlations. Therefore, A. mangium families with lower Y and y in heartwood could produce progenies with higher total phenol and total flavanol content, leading to higher natural decay resistance.