A coordinate measuring method was presented for the variable ratio noncircular bevel gear used in sliding-limiting differential in this paper. The path of the coordinate measuring was planned according to the feathers of the variable ratio noncircular bevel gear. And then generation and simulation of the measuring path was analyzed by software-Powermill. At last, the variable ratio noncircular bevel gear was measured by a coordinate measuring machine and the data was in good preparation for the later calculation and processing.