Abstract: There is a tremendous prospect of THz imaging in the safety testing，medical rsearch and nondestructive testing，etc.In the research using CW THz imaging technology to debond in space shuttle insulating foam，the noise severely affects the future image processing.By analyzing the characteristics of the stripe noise of terahertz image，an algorithm，based on that image projection of the spectrum automatically determines the frequency of noise，is presented，which uses ButterWorth band stop filter to deal with the stripe noise.The result shows that stripe noise is removed and the image details are reserved.