Abstract: According to the DEM data characteristics and the application needs of DEM network progressive transmission,a new progressive transmission method of DEM data based the improved JPEG2000 lossless-compression is presented.With this method,the accuracy of DEM data's accuracy in each resolution can be hold perfectly and the data can be compressed effectively and progressively.The 2/6 integer-to-integer wavelet basis is used to decompose DEM data.Using the precincts progressive compression method and the index file of the compressed code stream,the progressive transmission of DEM data is realized.It is proved that the original terrain characteristics are better maintained at different resolutions compared to the standard 5/3 wavelet basis.The transmitting data bytes are decreased to 90.29% compared to that of the traditional method in network progressive transmitting.