The development of ultrasensitive analysis technique for combination assay of cancer associated serum biomarkers is an effective method for early cancer screening and diagnosis[1].Meanwhile,surface-enhanced Raman spectroscopy(SERS),known as an ultrasensitive method even capable of detecting single molecule,has long been recognized as a powerful tool for trace biomarker analysis.SERS offers a unique "signature" spectrum profile with very narrow peaks for individual analyte,which possesses the capability to detect multiple analytes simultaneously[2,3].