Spydeberg is a municipality in Østfold county, Norway. The administrative centre of the municipality is the village of Spydeberg. It is divided into the parishes Spydeberg, Heli, and Hovin. Spydeberg was established as a municipality on 1 January 1838 (see formannskapsdistrikt).The village of Spydeberg has approximately 4,000 inhabitants. It is located 45 kilometres (28 mi) southeast of Oslo and is easily reached by a bus and a train line. There are 16 daily buses to Oslo, and about 12 train departures. A lot of the people in Spydeberg commute to Oslo for work.
The municipality (originally the parish) is named after the old Spydeberg farm (Old Norse: Spjótaberg), since the first church was built here. The first element is the plural genitive case of spjót which means "spear" and the last element is Berg which means "mountain". The word "spear" is here probably referring to some outstanding points of a nearby mountain.The coat-of-arms is from modern times. They were granted on 30 June 1978. The arms show three canting silver spear points (from the word spyd which comes from the Old Norse word spjót) on a red background. The model for the spear points was unearthed at a burial mound near Mørk in 1905. The three spears represent the three parishes in the municipality. It was designed by Truls Nygaard.