Abstract: We use teleseismic records of M≥6.0 earthquakes between September 2, 2011 to January 16, 2014 from 16 seismic stations of the Binchuan Active Source Study to get the P-wave receiver function information from every station, calculate and analyze changes of crust thickness and distribution of Poisson's ratios in the Binchuan region. Finally, we get a high spatial resolution result of the crust thickness in Binchuan region with an average value of 45.3 km, which shows v a characteristic of ‘deeper in the north and east part, shallower in th south and west part’. The deepest region locates in the Xiaoyindian Station with thickness of 47.9 km; the shallowest region in Paiying Station with thickness of 42.1 km. We find deeper Moho boundary nearby the Chenhai Fault and shallower nearby Honghe Fault; the isoline distribution of thickness changes greatly nearby Chenhai Fault and slowly nearby Honghe Fault. From the distribution of Poisson′s ratios, we find it’s unevenly in the study area with great difference from the north part to the south part, which shows a characteristic of ‘lower in the north , higher in th south’. The Poisson’s ratio nearby Honghe Fault is medium to high (0.26≤σ≤0.29); lower nearby Honghe Fault (σ≤0.26). We conclude that the possible reason of different characteristic between Poisson′s ratio and crust thickness is thicker in the upper crust of the Binchuan region.

Key words: Crust thickness, Poisson&apos, s ratio, Receiver function, The Binchuan region