The time taken to write a signal to a pixel is shortened in a display device. Further, a signal is written at high speed even when high voltage is applied. The display device includes a pixel including a transistor and a liquid crystal element electrically connected to a source or a drain of the transistor. The transistor includes an intrinsic or substantially intrinsic oxide semiconductor as a semiconductor material and has an off-state current of 1×10−17 A/μm or less. The pixel does not include a capacitor. Since it is not necessary to provide a capacitor, the time taken to write a signal can be shortened.