A substrate unit, a display device, and a method for manufacturing the display device are disclosed. The method for manufacturing the display device includes the steps of: providing a first carrier plate and forming a first interlayer on the first carrier plate; disposing a first glass substrate on the first interlayer to form a first substrate unit; forming a first device layer on the first glass substrate to obtain a first device substrate; providing a second carrier plate and forming a second interlayer on the second carrier plate; disposing a second glass substrate on the second interlayer to form a second substrate unit; combining the first device substrate with the second substrate unit; separating the first glass substrate from the first interlayer; and separating the second glass substrate from the second interlayer to obtain the display device.