In order to study the influence of notch characteristics on magnetic memory signals,measured the normal component of magnetic flux leakage Hp(y) of different notch specimens and the relationship between the magnetic field values at a fixed point with stress under different loads;carried ANSYS simulation on double associated notch specimen,studied the internal stress distribution of double associated notch specimen and studied the relationship between the magnetic field value at a fixed point with stress;compared the experimental results with simulation results and found that test results was consistent with the simulation results.The results show that semicircular notch is more potential danger than V-shaped notch specimen;magnetic field values at the center of notch of the double associated notch specimen is approximately superimposed on single notch specimen magnetic field values in corresponding position.The normal component of magnetic flux leakage Hp(y) and gradient value k(y) in stress concentration of double associated notch specimen no longer applicable of evaluating stress concentration degree of double associated notch.