Abstract: There has been accumulated massive storage waste rock on a molybdenum mine in Luonan.Pre-separation experiments by X fluorescence were conducted on materials with particle size of 20~150 mm，molybdenum grade of 0.051%，for comprehensive utilize of the resource and reduce environment influence caused by waste rock accumulation.Results indicated that pre-concentrate with molybdenum grade of 0.125%，yield recovery of 88.10%，and total recovery of 81.05% was obtained when excitation voltage of 45 kV，filter number of 6，feeding frequency of 27.5 Hz and the separation threshold of 0.42 by radiation sorting machine pre-separation.To provide technique basis for beneficiation of pre-concentrate，process mineralogy research was conducted.Main valuable mineral of pre-concentrate is molybdenite，96.56% of molybdenum exists in molybdenite.Gangue minerals are mainly feldspar，followed by quartz，garnet and calcite，etc.24.10% molybdenite distributed in +0.8 mm fraction，64.64% molybdenite distributed in -0.075 mm fraction after crushed to -1 mm.Stage grinding-stage separation process was recommended for reasonably recovery of the ore.

Key words: Stockpiling waste rock, X fluorescence pre-separation, Process mineralogy