Tumor derived-exosomes are an emerging noninvasive biomarker reservoirs that reflect biological information from their parental cells, especially specific markers, including proteins, DNA fragments and RNAs. Recently, analytical methods of tumor-derived exosomes are grow increasing. However, develop a convenient signal amplification technique to improve sensibility of exosomes detection still remains challenges. Herein, an ultrasensitive and specific exosomes diagnostic biochip is constructed and further applied to circulating tumor exosomes detection in serum. Using exosomes diagnostic biochip, signal amplification is achieved by combining the advantages of quantum dots with biomimetic periodic nanostructure of photonic crystals. Glypican-1 (GPC1), a membrane-anchored protein that overexpressed in exosomes from pancreatic cancer, is detected using nano-sized molecular beacons with high luminescence efficiency, following the signal is amplified through photonic crystals. Moreover, the method allowed the quantitative analysis of various disease-specific surface proteins on exosomes. We believe that this exosomes diagnostic biochip is likely having potential representing an effective bioassay, which may be helpful for quantification of disease-specific exosomes in clinical.