Data developed in support of the manuscript: evaluating ecosystem protection and fragmentation of the world's major mountain regions. Major mountain regions and their file abbreviations include: Alb=Albertine Rift; Alp=Alps; And=Andes; EaR=Great Eastern Ranges; Him=Himalayas; and Y2Y: Yellowstone to Yukon. Files: GlobalMountain_ecosystems.zip - spatial dataset (TIFF) with unique integer values encoded as: (landform * 10000) + (biome ID * 100) + (climate region ID). GlobalMountain_humanmod.zip - spatial dataset (TIFF) with values ranging 0.0 (not human modified) to 1.0 (human modified). GlobalMountain_protectedareas.zip - spatial dataset (TIFF) with integer values of 1 representing protected areas (IUCN categories I-IV). GlobalMountain_regions.zip - spatial datasets (shapefiles) of the regions with 0, 10, and 30 km buffer. GlobalMountain_samples.zip - tabular datasets (*.csv) of random samples within each region containing variables on: protected area, human modification, distance from ecosystem edge, ecosystem ID. Google Earth Engine code.