Sant'Elpidio a Mare is a town and comune in the province of Fermo, in the Marche region of Italy.

Sant'Elpidio a Mare is located on a ridge of Marche Apennine, elevation 251 metres (823 ft) above sea level, between the lower river valleys of the river Tenna and Ete Morto, 9 kilometres (6 mi) from the Adriatic Sea.

The historical name of locality is documented by an 11th century parchment as "Sancto Elpidio Majore" to distinguish it from other places in Sant'Elpidio Morico Brand Fermana.

The town occupies the site of the ancient Roman city of Cluana, destroyed by the Visigoths in the early 5th century.

In 887 here a large Benedictine Abbey was founded in 887; the medieval borough rose around it as Castello di Sant'Elpidio, starting from the 11th century.