We studied on texture analysis of SAR data by use of JERS1 SAR and LANDSAT ETM+. The Information entropy is applied to calculate a degree of mixture of texture. And differences of value on each land coverage is discussed in varying window sizes. Furthermore Principal Component Analysis, in which 5 bands of Landsat data, SAR's digital number and 3 types of entropy distribution are adopted as factors, had been exploited to evaluate entropy distributions' significance on being used in combination with optical sensor like LANDSAT ETM+ for the sake of extracting urban land surface characteristics.