The invention discloses a system for measuring geometrical characteristic parameters of a picture, and belongs to the field of application of computer assistant measurement analysis technology. The system comprises a position signal acquisition device, a data processor, a display screen, a function selector and a signal transmitter, wherein the signal transmitter is used to transmit the signal ofa position point selected by a user on the surface of the measuring picture; the position signal acquisition device acquires the signal of the position point transmitted by the transmitter from a picture area facing the position signal acquisition device so as to determine the area the user is interested in; the data processor receives the acquisition relative coordinate transmitted by the position signal acquisition device and converts the coordinate to the real relative coordinate, and according to the function selection signal provided by the function selector, the data processor processesthe real relative coordinate and sends the processing results to the display screen. The system adopts a digitized measurement method and allows the user to conveniently measure and compare the geometrical characteristic parameters of pictures the user interested in, such as distance, angle, shape and area, while reading pictures.