Nikaia-Agios Ioannis Renti () is a municipality in the Piraeus regional unit, Attica, Greece. The seat of the municipality is the town Nikaia. The municipality has an area of 11.173 km<sup>2</sup>.
The municipality Nikaia-Agios Ioannis Renti was formed at the 2011 local government reform by the merger of the following 2 former municipalities, that became municipal units: