The subject of my research is Magnetoelectric coupling effect in all oxide Ferromagnetic/Multiferroic heterostructures. Our purpose is to achieve the repeatable modulation of magnetic properties by electric field in ferromagnetic/multiferroic heterostructures. On this purpose, there are six works have been done until now. The first is about the anomalous thickness-dependent exchange bias effect in Fe₃O₄/YMnO₃ multiferroic heterostructures. As the exchange bias has brought unidirectional anisotropy to the heterostructures, we are interested about how did the exchange bias affect the anisotropic magnetoresistance of the heterstructures. However, it is a pity that the Fe₃O₄ changes to an insulator when the temperature is below the Verwey transition temperature. So we just studied the exchange bias effect modulated anisotropic magnetoresistance in Fe/YMnO₃ multiferroic bilayers. As a typical multiferroic, the stable state of YMnO₃ is in hexagonal (h) structure, while the manetoelectric coupling in h-YMnO₃ is not very strong as the ferromagnetic and ferroelectric properties are nonhomologous. So we prepared the metastable YMnO₃ with orthorhombic (o) by strain engineering. The o-YMnO₃ with distorted perovskite structure is friendly to most perovskite manganite, this will benefit the study of the interfacial coupling in the bilayers. We fabricated the o-YMnO₃ and La_0.6Sr_0.4MnO₃ heterostructures by radio-frequency and facing-target magnetron sputtering. We found that the interfacial coupling is strongly depend on the crystal orientation and the strain we bring to the heterostructures.