A thermoacoustic device includes a thermoacoustic module, a first protection component, a second protection component, and an infrared-reflective film. The thermoacoustic module includes a sound wave generator, at least one first electrode and at least one second electrode. The at least one first electrode and the at least one second electrode are electrically connected to the sound wave generator. The sound wave generator includes a carbon nanotube structure, and the first and second protection components are located on opposite sides of the sound wave generator. The infrared-reflective film is located on the first protection component.