This study focuses on the need to detect tangential stress within steel components.A dual-channel electromag- netic ultrasonic transducer was developed,and a high-precision stress measurement system based on shear wave birefrin- gence was established.The effects of different time-of-flight extraction methods in the time domain and various filtering algorithms in the frequency domain on stress measurement results were analyzed.Among these methods,the Butter- worth filter demonstrated the best performance,improving the signal-to-noise ratio by 1.3 times compared to the original signal,with a standard deviation of 0.7 in repeated tests.For time-of-flight extraction,the autocorrelation method proved to be the most stable,with a standard deviation of only 0.2 in repeated tests.Stress measurements were conduc- ted on two types of steel,Q345 and L360.Experimental results showed that the calibration curves for both materials a- chieved R²values exceeding 0.98,and the absolute error in stress measurement was less than 10 MPa.The electromag- netic ultrasonic stress measurement system based on shear wave birefringence developed in this study exhibits high accu- racy and stability.