The underground LHDs have performance and structural features differentto those of surface loaders.Due to these differences,a wide use of LHDs has been made inmines, and by now they have become a necessary ore removal equipment in some mines.The author compare underground LHDs with surface loaders with equal shovel capacityand explicates performance and strucural features of LHDs,including selection of perfor-mance parameters such as power,pull,push and breakout force etc,general arrangement,and structural features of Cab and engine.