The invention provides a method of continuously automatically reading transmission signal values of multiple developing microarray biochips, and a reading instrument and a reading system for realizing the method. The reading method is characterized by comprising: (1) scanning a glass chip bar code to obtain chip bar code information; (2) placing the main camera used for shooting a chip image and the background light source used for main camera lighting on two sides of a glass chip; (3) identifying parameters according to the bar code information, chip images and signal points, automatically identifying and positioning the signal points, and automatically obtaining signal point coordinates; (4) automatically obtaining signal values of the signal points according to the obtained signal point coordinates; and (5) automatically continuously reading a plurality of chips (which can be chips of different types) through position movement.