The multi-pulse accumulation detection can improve the receiving SNR.The echo delay can cause pulse stretching combining these two properties，a method for identifying the moving target and background with multi-pulse stretching is introduced.As the target speed changes the angle between optic axis and target surface，it causes the echo delay (pulse width)to change.The moving target can be distinguished from the background according to the shape different from the benchmark pulse.The simulation result shows that the more the pulse numbers and times of accumulation average are，the less the noise is，and the better the SNR is.The target and background can be distinguished efficiently by multi-pulse stretching，which can be used to measure the moving speed and location in real target detecting.