Finding new quantum states emerging out of complex interplay between various electronic degrees of freedom in strongly correlated oxides is one of the goals in condensed matter physics. In this regard, heterostructures provide a perfect platform where exotic quantum physical phenomena may arise due to charge/spin/orbital reconstruction at the interfaces. While the literature is abundant with reports on the polar oxide single perovskite heterostructures, in this thesis, we investigate the electronic structure of a set of non-polar complex oxide heterostructures: Sr2FeMoO6/La2CoMnO6 (SFMO/LCMO), La1-xSrxMnO3/BaTiO3 (LSMO/BTO), and Fe3O4/NiFe2O4 (FO/NFO) which constitute a metal-insulator interface. We find that while the SFMO/LCMO produces a spin-polarized 2DEG, LSMO/BTO is devoid of forming any new quantum state. For the ferrite heterostructure, we observe the thickness driven metal-insulator transition.