The research on ant diversity at tobacco plantation in Sago Malintang Natural Reserve, West Sumatra, had been conducted on September 2019. This study aimed to determine the diversity of ants at the study site. Ant specimens were collected by using Quadra Protocol applied within two transects that arranged in the middle of plantation and at its edge. As result, 23 species belonged to 17 genera, eight tribes and five subfamilies were identified from 592 specimen collected. Both parts of plantation had moderate ant diversity (H’=2.25). Myrmicinae was subfamily with highest species number recorded (10 species), followed by Formicinae (five species), Ponerinae (four species), and Dolichoderinae (three species), while Pseudomyrmecinae only with one species. Carebara cf. affinis was recognized as common species on both transects. Hand collecting and soil core, two techniques used in Quadra Protocol, performed prominently in collecting specimen in this study. Further detail on research result, transect at the edge of tobacco plantation yielded 460 individuals identified into 21 species, 16 genera, eight tribes and five subfamilies while the transect inside plantation recorded 132 individuals that determined to be from 10 species, nine genera, five tribes and four subfamilies.