Abstract: Laser-induced breakdown spectroscopy technology has some advantages such as smaller exciting spot size, conveniently analyzing for tiny defect, no special treatment on sample, shorter time for analysis and so on, so that it was applied on analysis of surface inclusions of steel extensively. By comparison of the spectrum intensity of characteristic elements in abnormal and normal parts of the samples, further judgment of characteristics can be made based on the previous information. The results of LIBS analysis have been verified by the analysis of energy disperse X-ray spectrum of scanning electron microscopy (SEM-EDS). So it is included that LIBS technology is suitable for the demands of analyzing and solving the defects rapiding on site.