A high resolution yaw sensor employed widely for observation the small angle measurements and angular applications. It needs to calibrate with high accuracy of standard for achievement of their performance and traceability. The measurement uncertainty evaluation of yaw sensor calibration is also necessary. This paper presents the technique of measurement uncertainty evaluation of yaw sensor following the guide to the expression of uncertainty in measurement (GUM). The uncertainty evaluations were approximately minimized to 40 arcsec, the confident level approximately 95%.
