Anhydrous minerals (olivine, clinopyroxene and orthopyroxene) from 12 peridotite xenoliths hosted by basalts in Hannuoba of Hebei were investigated by micro_Fourier transform infrared spectrometry (FTIR). No distinct OHabsorption bands can be found in olivines, whereas all the analyzed clinopyroxene (Cpx) and orthopyroxene (Opx) grains contain structural water in the form of OH. The structural water contents of pyroxenes show inhomogeneous distribution within individual grains characterized by higher contents in the core and lower in the rim. Low water contents at grain rims probably result from hydrogen diffusion after pressure decrease upon rock ascending. The range of the average core water content of multi grains (>10) from the same sample for the twelve Hannuoba peridotites is 48×10-6～152×10-6 and 20×10-6～55×10-6 for Cpx and Opx respectively. On the basis of water contents of the minerals and their volume proportions, the water contents of the whole rocks are estimated to be 11×10-6～48×10-6. Combined with the available data of peridotite xenoliths worldwide, it is held that, under the physical and chemical conditions of lithospheric mantlethe water partition coefficient between clinopyroxene and orthoproxene should be 2.2±0.6, and the water distribution in lithosphere seems to be heterogeneous both at global and regional scales.