Pd(en)2Cl2 intercalated graphite oxide was firstly synthesized by using Pd(en)2Cl2 as the Pd precursor and graphite oxide as the carbon precursor, and then graphene/Pd composites were prepared by reducing the intercalated graphite oxide with NaBH4. The structure of the composites is characterized by X-ray diffraction (XRD), field-emission scan electron microscope (FE-SEM), transmission electron microscope (TEM) and N2 adsorption test, and the formation mechanism of the composites is deduced based on the characterizations. Keywords ：graphite oxide; graphene; palladium; formation mechanism