Carboniferous Karashayi Formation of Tarim Basin formed in the continental shelf environment is composed of several sedimentary assemblages of clastic rocks, carbonate rocks and gypsum rocks. It is one of the important reservoir combinations in the Tarim Basin. According to the research results of paleontology, the formation can be approximately correlated with the Visean and Serpukhovian Stage of the International Stratigraphic Chart, about ±27 Ma. In this paper, the cyclostratigraphy was carried on well logs GR (Natural Gamma-Ray Log), SP (Spontaneous Potential Log), U, Th, K, etc.of Karashayi Formation with spectral analysis and wavelet analysis methods.