The ［(Ni80Fe20)1.4nm/Moxnm］30 magnetic multilayers(x=0.7,1.6,2.1) have been investigated by selected area electron diffraction and high resolution electron microscopy (HREM).It is revealed that:(a) The structure of the NiFe/Mo multilayer changes with the increase of the thickness of Mo spacer-layer. The NiFe and Mo layers are mainly amorphous as the Mo spacer is 0.7 nm in thickness, and crystallized into polycrystalline fcc NiFe and bcc Mo layers as the Mo spacer is thicker than 1.6nm. (b) For the multilayers with Mo spacer of 1.6nm and 2.1nm in thickness , there are two types of orientation relationship between the fcc NiFe and bcc Mo:(110)Mo∥(111)NiFe，［111］Mo∥［110］NiFeand(110)Mo∥(111)NiFe，［001］Mo∥［110］NiFe.(c) The NiFe /Mo interfaces are sharp in case (b) but the lattice spacing varies near the interface region as the lattice spacing of NiFe expands and that of Mo contracts with respect to their bulk counterparts. The variation of lattice spacing near the interfacial region has been discussed and the absence of giant magneto-resistance has been interpreted by the structural characteristics of the multilayers.