The invention discloses an echo signal detection circuit of an adaptive ultrasonic wave, wherein an echo signal docked by a pre-channel circuit is amplified and filtered, and a main channel circuit performs re-amplification processing and zero-crossing comparison to generate a main channel signal containing an interference pulse; an auxiliary channel circuit pre-receives the signal for peak detection and obtains a comparison level through attenuation according to a certain proportion, the official received signal is subjected with trigger comparison with the comparison level to generate a first pulse-sequence signal, a strobe signal is generated according to the falling edge of the first pulse for an AND-operation with the main channel signal, and a second pulse-sequence signal is output to trigger a timing module to stop timing to obtain a time difference. By adopting a peak detection circuit and cooperating with a working mode of two consecutive times of signal reception and transmission, the echo signal detection circuit provided by the invention dynamically tracks the pre-received signal and flexibly adjusts the comparison level, which solves the pulse-sequence skipping problem. In addition, the strobe signal is functioned to avoid the effect of the noise pulse of the main channel on the time measurement, and the main channel uses a zero-crossing comparator to solve the problem of phase lead or lag in the quarter period of the pulse sequence.