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The non-smooth morphology of pigeon surface was analyzed. The three dimensions information of the surface of pigeon's back, breast and wing were obtained using 3D scanner laser system. The surface was analyzed based on fractal geometry. The surface dimension and linear dimension were calculated using box-counting method, and their distributions were analyzed. It showed that the surface of back,，breast and wing all display fractal feature. The range of surface dimension is between 2.8988 and 2.9788, and the range of liner dimension of these three parts is between 1.0002 and 1.0247. The study can provide the basis information for further quantitative analyzing the drag reduction mechanism of the surface of pigeon in the air.