Santa Maria Rezzonico was a commune in the Italianprovince of Como on the north-west shore of Lake Como immediately to the north of Sant'Abbondio and south of Cremia. The territory of the commune, which had an area of 11 km², also bordered with Plesio and (across the lake in the province of Lecco) Bellano and Dervio.
In 2001 the population was 1,088, giving a density of 99 inhabitants/km².
On 1 January2003 Santa Maria Rezzonico merged with Sant'Abbondio to form the new commune of San Siro.
