Ioannis Antonopoulos (Greek: Ιωάννης Αντωνόπουλος, 1810 - October 28, 1882) was a Greek politician and a mayor of Patras.

He was born in Patras and was the son of Dimitrios Antonopoulos.

He later studied law in Corfu and worked as a judge.

He was elected several times to the public council and attempted to become president of the municipal chamber.

He was elected six times as parliamentary representative of Achaia and served as Speaker of the Hellenic Parliament.