A multi-channel hemispherical ultrasonic wave transmit and receive detection system and method, wherein, a transmit control system transmits out a plurality of detection signals through an energy converter, a receive system receives the reflected signals reflected from an obstacle, in determining a channel used by said transmit control system to control a multiplexer to select a channel to switch to and then amplify said reflected signals. Then, said receive system performs high speed analog-to-digital sampling, and high speed transmission through USB for said reflected signals amplified. Finally, a Graphic User Interface (GUI) of a computer performs smooth-out processing for said reflected signals and displays its waveforms, in determining distance to said obstacle.