The Decentralized Administration of Peloponnese, Western Greece and the Ionian (Greek: Αποκεντρωμένη Διοίκηση Πελοποννήσου, Δυτικής Ελλάδας και Ιονίου, romanized: Apokentroméni Dioíkisi Peloponnísou, Dytikís Elládas kai Ioníou) is one of the seven decentralized administrations of Greece, consisting of the regions of Peloponnese, Western Greece and the Ionian Islands.

Its seat is in Patras, Western Greece, and it is currently headed by Acting Secretary-General Dionysios Panagiotopoulos.

[3] They enjoy both administrative and financial autonomy[1] and exercise devolved state powers in urban planning, environmental and energy policy, forestry, migration and citizenship.

The Decentralized Administration is led by a Secretary-General (Γενικός Γραμματέας) who is appointed or dismissed by a Cabinet decision upon request of the Greek Minister of Interior,[5] and is therefore considered the senior representative of the national government in the regions.

Following the electoral victory of Syriza in January 2015, the new Minister for the Interior, Nikos Voutsis, declared that the decentralized administrations would be abolished, and their powers transferred to the regions.