A microarray detection platform was reported based on the principle of evanescent wave. The platform is developed for the detection of the fluorescent-labeled nucleic acids on DNA microarrays by using the evanescent wave created by total internal reflection. The fluorescence emission is collected by a COD device, and then it is converted to digital images. Quantitative data of the interactions on microarray can be extracted from the analysis for these images. Experiments demonstrate that the detection system has good sensitivity and it is comparable with commercial biochip scanners.