An environmental control device includes a shaft installed in an aircraft and coupled to a motor to be rotatable; a compressor connected to the shaft to be rotatable, the compressor adiabatically compressing external air introduced into the aircraft to form a flow of compressed air having a raised temperature; a heat exchanger allowing heat exchange between the compressed air having a raised temperature and a portion of the external air introduced into the aircraft; and a turbine connected to the shaft to be rotatable, the turbine adiabatically expanding the heat-exchanged compressed air to form a flow of chilling air.