PURPOSE: To obtain an ultrasonic distance measuring equipment for measuring the distance between vehicles while discriminating the forward ultrasonic wave from other ultrasonic waves by providing two ultrasonic receivers with receiving sensitivity angle distributions symmetrical with respect to the traveling direction of transmission wave.

CONSTITUTION: When a preceding vehicle is present, a transmission wave from a transmitter 10 is reflected on the preceding vehicle and a part of reflected wave travels reversely to the transmission wave. Since the reflected wave travels in the direction making a same angle with receivers 11, 12, when the receiving sound pressures thereof are amplified through amplifier circuits 14L, 14R and the components having same frequency as the transmission ultrasonic wave are detected through BPFs 15L, 15R and compared through a sound pressure comparison circuit 16, the difference of sound pressures is lower than a predetermined value. When two sound pressures are added through a sound pressure adder circuit 17 and a comparator 18 decides that the sum of sound pressure is higher than a predetermined value, a circuit 19 calculates the distance up to the preceding vehicle based on the receiving time of sound pressure from the comparator 18 and the transmitting time of driving voltage to a drive circuit 13.