Established the analytical method by using ultrasonic vibration - suspension of solid sampling graphite furnace atomic absorption spectrometry (GF-AAS) to test trace mercury in the titanium dioxide, by choosing a suitable concentration of agar solution as dispersing agent, and taking the ultrasonic oscillation technique to prepare uniform and stable titanium dioxide suspended solid solution, and finally using the solid injection sampling GF-AAS method to test trace elements of mercury.. Through the application of solid injection technique, the problem that the titanium dioxide is extremely difficult to digest and mercury volatile loss are solved and the matrix effect of the high titanium is eliminated by standard addition method as well. The paper has tested the conditions of preparation of solid suspension such as agar dispersing agent concentration, dosage, and ultrasonic vibration parameters. and titanium dioxide solid suspensions obtained by the method have the characters of uniformity, stability, mobility features, and preserve a long time. Graphite furnace testing procedures are also optimized: drying temperature 85 °C, time 30 s, by lowering the drying temperature and measures to extend the time to solve the contradiction of water evaporation and mercury volatilization; cancel the ashing step directly into the atomization stage in order to avoid mercury loss after drying. Finally, set atomic temperature 1 000 °C, for 5 s and close the purged argon flow of the internal graphite tube to ensure mercury exists as different forms such as free, particle adsorption or parcels can be effective tested. The detection limit is from 0.000 to 005% and recovery rate is from 93% to 109%, RSD <3.1%. The results of the test is correspond with that of Microwave Digestion and Inductively Coupled Plasma Mass Spectrometry method. The methods can meet the requirement of testing toxic trace elements mercury in high-grade titanium dioxide which used in medical, food, ceramics and other field.