We fabricate a hybrid fiber composed of a multi-mode, silica-based fiber and a GdFe thin film adjacent to each other. Magneto-optical (MO) signals modulated by AC magnetic fields on the GdFe layer are detected at the output pupil of the fiber, showing that the polarization state of the propagated light in the mixed-mode condition can be well defined. We find that local modulation of magnetization at different positions of the GdFe layer results in MO signals at the different position of the output, showing the spatial de-multiplexing of polarization modulated signals.