A display device and a wearable device are provided, including: a middle frame assembly, including a fixed middle frame and a first sliding middle frame slidably connected, the fixed middle frame and the first sliding middle frame sliding relatively along a first direction and together enclosing a middle frame assembly cavity; a flexible display screen including a first free portion corresponding to the first sliding middle frame, with the first free portion being curled and concealed; a synchronized expansion mechanism located within the middle frame assembly cavity, with a fixed pivot shaft extending along a second direction; a first transmission component, fixedly connected to the first sliding middle frame with one end and movably connected to the fixed pivot shaft with another end; and a first winding component fixedly connected to the first free portion with one end and retractably connected to the fixed pivot shaft with another end.