A new non-destructive testing techn iq ue is investigated from the point of view of engineering application,that is the defect inspection in workpiece by Compton scattering.The significance of Compto n scattering for defect inspection is pointed out.The inspecting principle and t he mathematical model are analyzed.Meanwhile,the vacuum ionization chamber is em ployed for the primary experiment of Compton scattering inspection with the expe riment results analyzed.Moreover,the research emphasis and the applying outlook are pointed out.It is indicated through practice that the Compton scattering tec hnique processes the advantage of flexible structure and high sensitivity,which is unique predominance in some special cases.It goes without saying that it is v ery significant to carry out further research for application.