Abstract: Using GIS and grid methods, the digital landform patterns were studied in Qinling Mts., based on the DEM data with grid precision of 100 m×100 m. The main ridge of Qinling Mts. was firstly abstracted as the reference boundary of north-south slope. Then the landform classification index was established and 4 km² was calculated as the optimal statistical unit of landform relief in Qinling Mts. Lastly the relief data and elevation data were fused and the results of digital landform patterns of Qinling Mts. were formed after data classification and encodment.The spatial distribution of landform patterns of Qinling Mts. was specified and the 15 mountain landforms were obtained by high precision grid data.They are concordance with the former research achievements with the scale of 1 000 000 in this area.

Key words: grid precision, GIS, digital landform pattern, Qinling Mts., grid precision, GIS, digital landform pattern