Alginate/polyacrylamide hybrid hydrogel has attracted intense interests in different fields, but the low tensile strength and stiffness limit its comprehensive application. In this hydrogel system, the alginate-cation network plays an important role. Thus, based on the unique structure of alginate and its special interaction with different metal cations, we designed a new method of introducing barium and ferric ions together to crosslink the alginate sufficiently, creating a stronger alginate network. As a result, the prepared hybrid hydrogel exhibits enhanced strength and stiffness, which may serve as a new way to develop stronger hydrogel.