Disclosed are a method and device for measuring a headcount by using a peak value distribution pattern of a radar reception signal according to the headcount. The method for counting people by using a UWB radar disclosed herein comprises: a step of computing, for each predetermined headcount, an amplitude probability density function based on the distance between a reflection point and a radar, by using a sample radar reception signal for the headcount; a step of calculating likelihood values with respect to the headcounts from a measured radio reception signal by using the probability density function; and a step of determining a headcount corresponding to the largest likelihood value among the calculated likelihood values, as a final headcount with respect to the measured radar reception signal.