Abstract: A new type of integrated optical waveguide magnetic field probe was proposed for electromagnetic compatibility test. The probe head is constituted with a LiNbO3 optical waveguide modulator and a doubly-loaded loop antenna element. The magnetic field information can be obtained by detecting the output optical intensity. Compared with the traditional magnetic field probes, it has lower disturbance of measured field, and can suppress the electrical influence effectively. Simulation result is consistent with the theoretical analysis.