Abstract: Cu-Fe based diamond composite was sintered in a vacuum pressed sintering furnace,and Scanning Electron Microscopy,Energy Dispersive Spectrometer,X-ray Diffraction were used to investigate the bonding interface between diamonds and sintered matrix.The results showed that Fe atoms of the sintered matrix diffused to the diamond surface,and a certain thick diffusion layer of CFe15 had been formed between them under the conditions of sintering temperature 930 ℃ and pressure 15 MPa,the diffusion layer seems to distribute in a non-continuous layer form which achieve a chemical bond between diamonds and the sintered powder metal matrix.