This research focuses on using silica nanoparticles prepared from rice husk ash and commercial nano silica to successfully produce PMMA/Sio2 nanocomposite with various Sio2 weight loadings (0.05, 0.1, and 0.15 % wt.). The samples were manufactured by utilizing an ultrasonic machine and a solution mixing. The characterization of the resulting PMMA/Sio2 nanocomposites were investigated using hardness, impact testing, flexural strength, and SEM.. The results showed that the best value percentage of RH is (0.05wt%) for Impact strength and (0.05wt%) for flexural strength, which gives the highest strength .and The best value percentages that gives the highest strengths for NP is (0.05wt%) for Impact strength and (0.1wt%) for flexural strength. SEM were also tested to find the structure of Sio2 and dispersion quality.