In this research, titanium dioxide (TiO2) nanoparticles were synthesized through green chemistry using a plant extract, obtained from lemongrass (Cymbopogon citratus) leaves.Two different methods for the leaf extraction were used, allowing the formation of smaller nanoparticles as well as obtaining a greater amount of the product via synthesis.The first method was the synthesis with ultrasound-assisted green chemistry, which used a precursor solution of titanium tetra-isopropoxide, obtaining nanoparticles of 20.01 nm in size and a production of 0.05 g of TiO2 nanoparticles via synthesis; the second method was based on the modification of the synthesis method using ultrasound-assisted green chemistry through the application of the pure precursor (titanium tetra-isopropoxide), obtaining nanoparticles with an average size of 18.67 nm and a production of 1.00 g of TiO2 nanoparticles via synthesis.According to the results, the best synthesis method used the pure precursor, obtaining nanoparticles of a smaller size and a production 20 times greater than the one obtained with the method using the precursor solution.As a result, future studies will benefit by optimizing the production process, reducing the environmental impact by using less reagents, maximizing the extraction of terpenes and flavonoids from lemongrass leaves and obtaining nanoparticles with sizes similar to those available commercially.