Abstract: The agglomeration of nano-SiO2 particles was improved by ultrasonic dispersion and adding dispersing agents to protect the newborn nano-particles. The dispersed nano-SiO2 particles can improve the fluorocarbon finish property. The experimental results indicate that the best time of ultrasonic dispersion was about 30 minutes, and KH570, CH hyper-dispersant and BYK-163 were selected as dispering agents, the performance of KH570 was the best. Both the mechanical properties and the ability to resist chemical reagent of modified fluorocarbon finish were improved and could meet the national standard.