Auburndale is a city in Polk County, Florida, United States. It is part of the Lakeland-Winter Haven, Florida metropolitan statistical area. Its population was 15,616 at the 2020 census.

Auburndale was founded in 1880 by Frank Fuller, who was seeking refuge from chilly winters in the Northeast United States. The place was originally named Sanatoria, from a hotel located there. When the railroad arrived in the 1880s, the town was renamed Auburndale at the suggestion of settlers from Auburndale, Massachusetts. The New England town had been named from the opening line of the poem "The Deserted Village" by Oliver Goldsmith. Early on, the city became a chosen destination for a number of America's most prominent artists.

The city is located 40 miles (64 km) northeast of Tampa and 59 miles (95 km) southwest of Orlando. Auburndale is located within the Central Florida Highlands area of the Atlantic Coastal Plain, with a terrain consisting of flatland interspersed with gently rolling hills.

According to the United States Census Bureau, the city has a total area of 9.3 square miles (24 km²), of which 4.1 sq mi (11 km²) (43.87%) are covered by water.

Auburndale is located in the humid subtropical zone, as designated by (Köppen climate classification: Cfa).

The city commission is made up of five commissioners elected from single-member districts. The mayor is elected from the commissioners by the voters. The city budget was $69 million in 2010.

As of the 2020 census, Auburndale had a population of 15,616. The median age was 40.0 years. 23.6% of residents were under the age of 18 and 17.3% of residents were 65 years of age or older. For every 100 females there were 93.9 males, and for every 100 females age 18 and over there were 90.8 males age 18 and over.

98.8% of residents lived in urban areas, while 1.2% lived in rural areas.