The main purpose of the paper is to describe the design of the near-infrared blood-oxygen monitorwith duallight sources and dual detectors, and the monitor can detect the blood-oxygen parameters of two sides of the local brain tissue. The monitor has two lamp s, they are lightened alternately by the pulse sequence, which make the monitor achieve the function of dual detectors. At the same time, the apparatus can monitor the brain blood-oxygen parameters of the patients continuously in real time, and output the curves of the blood2oxygen parameters of two sides of brain tissue.