Nails are a simple and viable solution to connect sections of wooden structures. Although they are the oldest and most traditional connection elements there is a considerable knowledge gap concerning the use of larger sized, threaded nails, in tropical hardwoods. The objective of this project was to evaluate the effect of different nail models and diameters on the withdrawal resistance of Allantoma decandra wood and verify the efficiency of the existing nail withdrawal resistance prediction equations. Withdrawal tests were carried out using three nail models (smooth, helical, and annular), of two different diameters (2.8 mm and 3.5 mm). For each combination, ten Allantoma decandra wood specimens were used. Four nails were inserted 3.2 mm into each wood specimen and then withdrawn using a universal testing machine with 600 kN capacity, according to the procedures of ASTM D-143-2014. The nail model was the most relevant factor in this study, having a direct influence on withdrawal resistance. Annular nails presented the highest resistance values, followed by helical and smooth nails. The nail diameter had no significant effect on the maximum load result. The equations for withdrawal resistance prediction demonstrated considerable accuracy regarding the experimentally obtained data, being important tools to anticipate the behavior of wooden structures.