Flexible glass with high bending strength is a remarkable component of flexible electronic displays. However, flexible glass is a brittle material inherently, and its mechanical properties still do not meet the requirements of application. To address this challenge, the application of chemical strengthening stands out as a viable approach to significantly bolster scratch resistance and bending strength in flexible glass. 90 μm ultra-thin high-aluminum flexible glass was reinforced in the molten potassium nitrate using a conventional one-step chemical strengthening method. The effect laws of chemical strengthening temperature and time on the surface stress, Vickers hardness and bending radius of the strengthened flexible glass were investigated. The results indicate that, after ion-exchange at 380 ℃ for 1 h, the compressive stress of sample reaches 834.12 MPa, and the depth of stress layer is 15.91 μm, at which time the glass samples have the best bending performance and scratch resistance. After chemical strengthening, the bending radiu of 90 μm flexible glass reduces from (29.8±0.73) mm to (6.94±0.99) mm. As the overly increasing exchange temperature and excessive prolongation of time, the mechanical properties of flexible glass are weakened.