In this manuscript we designed, fabricated, and tested a novel microfluidic device for continuous and real time separation of plasma from whole blood based on plasma skimming effect and microcentrifugal effect using microchannels and microstructures. The microdevice was fabricated by micro electro mechanical system (MEMS) technology, which was made of a silicon wafer with a single step of deep reaction ion etching and a PDMS-glass cover. The process of plasma separation was implemented continuously without problems of clogging or jamming. The plasma selectivity of 95.36% is obtained under the optimal conditions. This microdevice has the potential to integrate into micro total analytical system (μTAS) with the advantages of low cost, short analytical time, disposability, low reagent and sample consumption, which will create a microanalysis system for point-of-care diagnostics.