A testing apparatus for a flexible screen includes a slide rail, a reel, and a clamping member. The reel is disposed at an end of the slide rail in the extension direction of the slide rail which the axial direction of the reel is perpendicular to. The reel has a hollow structure and is connected to a evacuating device through a gas path formed in the hollow structure to enable the evacuating device to vacuumize inside of the reel to fit the flexible screen and coil around the reel. The reel is configured to affix first end of flexible screen and rotate to coil the flexible screen. The clamping member is configured to clamp a second end of the flexible screen opposite to the first end. The reel is further configured to rotate to drive, through the flexible screen, the reel and the clamping member to slide towards each other along the slide rail.