The invention discloses a method for rapid detection of the content of an SBS modifier in SBS modified asphalt, wherein the method comprises the following steps: preparing a series of modified asphalt standard samples with different SBS contents, and detecting Raman spectra of the samples in the range of 500-3000 cm<-1> by using a portable laser Raman spectrometer. According to a fact that the ratio of the SBS Raman spectral characteristic absorption peak area at 966 cm<-1> accounting for the characteristic absorption peak area of matrix asphalt at 1600 cm<-1> is in direct proportion to the content of the SBS, the SBS in the SBS modified asphalt is quantitatively detected. The method has the advantages of portable detecting instrument, simple operation, low cost and good reproducibility, is suitable for engineering on-site detection, is easy to popularize and generalize, and has good application prospect.