Abstract: By means of spectrometry technology and chemical analysis and test in typical oil and gas seepage areas in Wuerhe area of Junggar basin, the paper discusses the abnormal spectral characteristics caused by the seepage and its relationship with and alkane contents. The results show that on the macroseepage abnormal spectrum of different alkane contents, W-shaped and double absorption peaks ranging from 2 310 to 2 350 nm are stable and single absorption peaks vary largely around 1 725 nm and 1 760 nm; the hydrocarbon absorption characteristics of microseepage are not obvious due to low hydrocarbon contents, but obvious clay alteration can be observed from rock thin sections and spectra. The clayization resulted from oil and gas seepage is dominated by montmorillonitization and illitization in Wuerhe area. Based on the measurement and observation of clay spectra caused by oil and gas seepage of different degrees, it is found that the depth of absorption peak of hydroxyl is large around 2 210 nm on the clay spectrum resulted from strong oil and gas seepage, whereas the depth of absorption peak is relatively small around 2 210 nm on the clay spectrum caused by weak seepage. The depth of absorption peak can reflect the intensity of oil and gas seepage indirectly. Based on the statistics of width, depth, area and symmetry of absorption peaks around 2 310 nm ( the left peak of W-shaped and double absorption peak) on oil sand spectrum and analysis on chromatography-mass spectrometry of saturated hydrocarbons, it is found that there is a linear relationship between the depth of absorption peak and alkane content of oil sand, and alkane contents can be estimated with the parameters of absorption peak depth through a matched linear expression, which could provide references for regional petroleum prospecting