Nyborg Municipality is a municipality in Region of Southern Denmark on the east coast of the island of Funen in central Denmark. The municipality covers an area of 278 km², and has a total population of 32,009. It borders Kerteminde Municipality to the north-west, Faaborg-Midtfyn Municipality to the south-west, Svendborg Municipality to the south and is connected to Slagelse Municipality by the Great Belt Bridge. Its mayor is Kenneth Muhs, a member of the Venstre political party. The main town and the site of its municipal council is the city of Nyborg.
The municipality was formed in 2007 as a result of the 2007 Municipal Reform, where the former Nyborg Municipality merged with Ørbæk and Ullerslev Municipality.
The island of Sprogø lies in the Great Belt c. 8.5 kilometers from the shores of the town of Nyborg. The Great Belt Bridge connects the municipality to the island, and then it continues to the island of Zealand at the town of Korsør.
Holckenhavn Fjord cuts into the municipality on its eastern shore, north of the castle of Holckenhavn. A road connects the municipality across the fjord.