The present invention relates to a human body detection sensor using a Doppler radar, comprising: a Doppler radar unit transmitting a Doppler radar signal and receiving the transmitted Doppler radar signal so as to output a signal processing result corresponding to a frequency difference between both signals; a filtering and amplifying unit for filtering out, from the signal outputted by the Doppler radar unit, a frequency band preset so as to correspond to a vibration generated by the internal bioactivity of a human body, and for amplifying the filtered signal; and a determination and control unit for determining whether a human body is detected by analyzing the signal outputted by the filtering and amplifying unit, and for outputting the determined result signal when the human body is detected.