Based on a type 3001 gear measuring machine equiped additionally with a computer, a printer, a drafting instrument, a digital control box and a series of software, the multi-function gear measuring machine is composed. The computer control, grating measurement, multi-parameter dynamic display, automatic drafting and printing and evaluation of precision grade are adopted by the system. It can do the auto-measurement and auto-evaluation for main errors of the cylinder gear and it can be fitted for technology reform of coordinate gear measuring instrument.