Ponnani (Malayalam pronunciation: [pon̺ːɐːn̺i]) is a municipality in Ponnani Taluk, Malappuram District, in the state of Kerala, India. It serves as the administrative center of the Taluk and Block Panchayat of the same name. It is situated at the estuary of Bharatappuzha (River Ponnani), on its southern bank, and is bounded by the Arabian Sea on the west and a series of brackish lagoons in the south.
It is the seventh-most populated municipality in the state, the second-most populated municipality in the district, and the most densely populated municipality in Malappuram district, having about 3,646 residents per square kilometre as of the year 2011. As of the 2011 Census, the municipality forms a part of Malappuram metropolitan area.