Abstract: Correlated oxides provide one of the richest platforms for exploring emergent quantum phenomena arising from strong coupling among charge, spin, orbital, and lattice degrees of freedom. Over the past few decades, ionic manipulation has emerged as a versatile strategy for tailoring correlated oxides. By driving the migration, insertion, extraction, and substitution of mobile ions, ionic manipulation enables the dynamic reconstruction of chemical composition, crystal structure, local coordination environments, and electronic states, providing new opportunities for stabilizing metastable phases and engineering emergent correlated quantum states. This review summarizes recent advances in the ionic manipulation of correlated oxides, with particular emphasis on oxygen-ion insertion/extraction, hydride substitution, and proton intercalation. We discuss the underlying mechanisms governing these ionic processes, including charge compensation, structural reconstruction, local crystal-field modulation, and correlated electronic-state evolution, together with their implications for iontronic functionalities. Finally, we highlight the major challenges and future opportunities for this exciting field.