The Lanhe metamorphic rocks in northern Guangdong province include mainly biotite-granulitite and muscovite-chlorite-schist. Based on their main elements, trace elements and rare earth elements, the original rocks of the biotite-granulitite and muscovite-chlorite-schist were recovered to be sandstone and mudrock, respectively, which may have deposited in passive continent margin. The facts that the youngest U-Pb age (725Ma) of detritus zircons from the biotite-granulitite and that metamorphism occurred at the Caledonian or earlier than the Caledonian Period suggest that the original sedimentary rocks of metamorphic rocks may have deposited at Early paleozoic. The Sm-Nd isotope compositions of the Lanhe metamorphic rocks also indicate that the provenance for the sedimentary rocks was composed of Paleo-proterozoic crust where there was little mantle-derived juvenile crustal matter.