An experimental platform of good polarization control performance is designed for the fiber magneto-optical (MO) effect and four wave mixing (FWM), in which the states of polarization (SOPs) of input optical signal and the MO coupling coefficient of nonlinear fibers are respectively controlled by a self-made electromagnetic polarization controller (EMPC) and a fiber-embedded toroidal coil. The dependency of fiber FWM idler power on the SOP ellipticity of input signal is measured and the experimental data are consistent with the theoretical results. And then, the MO-FWM experiment is implemented and the variation of fiber FWM idler power with the applied magnetic field is obtained.