Abstract: The effects of solid solution cooling mode and aging temperature on the microstructure and tensile properties of TB8 titanium alloy were investigated. The results show that the width of the secondary α phase precipitated under water cooling after solution treatment is slightly smaller than that of air cooling at the same aging temperature. As the aging temperature increases from 530 ℃ to 590 ℃, the width of the secondary α phase precipitated by air cooling and water quenching increases by 0.32 μm and 0.27 μm, respectively. The length of the α phase becomes longer and crosses into a network. With the increase of aging temperature, the strength of the alloy decreases, and the plasticity of the alloy shows the opposite trend. The highest yield strength is obtained after the alloy is treated with water-cooled at 830 ℃ and air-cooled at530 ℃, and reaches 1087 MPa.