This study was to evaluate the selected performances of modified Ludai (Sapium Baccatum) and Kelempayan (Neolamarckia Cadamba) wood species. Ludai and Kelempayan were impregnated with acetic anhydride at 80°C, 100°C, and 120°C for 15, 30, 60, 180, 300, and 420 min without catalyst. The highest WPG of 16% and 14% for Ludai and Kelempayan were obtained. VC% ranging from 0.5% to 10% were obtained. The ultimate OH-groups substituted of acetylated Ludai and Kelempayan at 120°C were 3.77 mmoles/g and 3.98 mmoles/g, respectively. Unlike the conventional preservative treatment in the industry today, wood-acetyl bonds pose a positive impact on the ecosystem.