The characteristics of Moir􀆧 signal and the positioning accuracy of turntable is sensitive to eccentricity and inclination. A research on the effect of eccentricity and inclination on the Moir􀆧 signal of grating of turntable in this paper. The working principle of turntable angular measurement system is described and the principle of separation method of Moir􀆧 signal characteristic is elaborated in detail. The error sources of Moir􀆧 signal are analyzed, the effect model of eccentricity and inclination are established respectively, and the relationship among the harmonic order of Moir􀆧 signal characteristic, eccentricity and inclination is deduced. The separation method of Moir􀆧 signal characteristic is implemented using a laboratory-made field-programmable gate array circuit. The result of experiment performed on the eccentricity and inclination test platform confirmed that eccentricity and inclination have linear relationship with first and second harmonic of Moir􀆧 signal characteristic, and nonlinear error is 3. 88% and 2. 08%.