Abstract: The single crystals of CdxZn1-xSe were prepared by chemical transport method. We change the luminescence center of the information carrier through adjusting the composition of the alloy quantum dots. The alloyed nanocrystlas show composition-tunable optical band gap energy and their emission can be tuned continuously in the range of 524 to 627 nm．Here,we discussed the multicolor optical coding for engineering assays through coating different-colored quantum dots onto the anti-fake label,which further resulting in a new security identification system. The multiple luminescent CdxZn1-xSe quantum dots based anti-fake system can be applied to supermarket labeling,military security and object identification.