To address the problem of accuracy loss of embedded angular displacement sensor after long time use, a self-calibration method using single probe error phase shift method is proposed in combination with the structural characteristics of the sensor. Firstly, the sensor error characteristics are analyzed based on the Fourier transform according to the principle of circumferential spatial closure. Secondly, the sensor error model is constructed by transforming the error sequence and solving the function relationship between the error and the starting reference with the sequence of starting measurement values as the starting reference for error offset. Finally, the online calibration experiment platform is established for verification experiments. Experimental results show that the single intra-pole error results are consistent with the measurement error characteristics, and the whole cycle measurement error is reduced significantly, with the error peak value reduced from 127. 80″ to 5. 90″. Comparison experiments and repeatability experiments show that the calibration efficiency of the method is improved by 80. 69% compared with the comparative calibration method, and the error distribution is concentrated after calibration, while remains good measurement stability. The self-calibration method described in this article effectively solves the problem of sensor accuracy loss without relying on a high-precision reference apparatus, and has important application significance for realizing the self-calibration of embedded angular displacement sensors.