A child safety seat includes a seat body, a headrest mechanism, an illumination device, and a power supply device. The headrest mechanism is connected to the seat body. The headrest mechanism includes a main body and a side wing. The side wing is movably connected to the main body. The illumination device is disposed on the side wing. The power supply device is electrically connected to the illumination device and is disposed separating from the side wing. The power supply device is used for providing electrical power to drive the illumination device to emit light.