The ability of titanium dioxide nanoparticles (TiO2 NPs) to attenuate and control several microorganisms was studied, especially for a disease that affects the health and productiveness of crops. For this purpose, the antifungal capacity of TiO2 nanoparticles obtained from two synthesis procedures was evaluated: the first procedure involved green chemistry using an aqueous extract prepared from African palm oil (Elaeis guineensis Jacq.) leaves; the second procedure followed the Pechini sol-gel method. The nanoparticles obtained by the green chemistry method and the Pechini sol-gel technique had average sizes of 14.60±0.44 nm and 12.30±0.54 nm as determined by scanning electron microscopy (SEM), respectively. The antifungal properties of TiO2 NPs were evaluated on the fungus Fusarium solani Mart. isolated on Sabouraud culture medium. A factorial experimental design was implemented with two variables: (1) exposure time ranging from 24, 48, and 72 h; (2) nanoparticle concentration between 100 and 400 mg L-1. All measurements were performed in quintuplicate. The results show that the TiO2 nanoparticles synthesized by the Pechini method inhibited the fungus by 96.16±0.85% with a nanoparticle concentration of 400 mg L-1, while the TiO2 nanoparticles obtained from the green chemistry method generated a high inhibitory activity of approximately 98.51±0.02% at the four experimental concentrations.