Guardamar del Segura (Valencian: [ˌɡwaɾðaˈmaɾ ðel seˈɣuɾa]), or briefly Guardamar, is a municipality of the province of Alicante located at the mouth of the river Segura in southern Valencia (autonomous community), Spain. It is a Mediterranean resort, with a large pine forest abutting an 11-km-long white sand beach.

Historically, it was an area of fishermen and farmers. A Phoenician colony, called Herna by Roman geographer Avienius in his book Ora Maritima was the first settlement near the mouth of Segura river, In Valencian, guardar means safekeeping and mar means sea, and this is another possible basis for its current name.

Guardamar is the southernmost Valencian-speaking town and in 1991 41.8% of the town's residents could speak it. Guardamar is also the only municipality of the Vega Baja del Segura comarca (known locally as Baix Segura) where Valencian is traditionally and widely spoken.

Guardamar hosts local festivals like Moros i Cristians (Moros y Cristianos), L'Encantà, and Fogueres de Sant Joan (Hogueras de San Juan), which commemorate its history.

The INE (Spanish Census) of 2006 showed that the city had 14,261 residents. By January 2011 this figure had reached 16,863 of which 10,051 were Spanish. The total dropped by 2015 to 15,589. The most prominent nationalities in 2015 were:

Historical population (1857-2015) Year Population Year Population 1857 2,696 1960 4,586 1887 2,549 1970 4,715 1900 2,862 1981 5,708 1910 2,898 1991 7,513 1920 3,067 2001 9,944 1930 4,016 2004 12,215 1940 4,703 2007 15,132 1950 4,704 2011 16,683 2015 15,589

Foreign population (official data, 2015) Nationality Percentage  United Kingdom 8,93  Russia 3,49  Bulgaria 2,24  Germany 2,02  Ukraine 1,92  Morocco 1,71  Romania 1,37  China 0,84  Italy 0,76

Carmen Verdú is the mayor of the city. In the latest municipal elections of May 2011, Carmen Verdú of the People's Party (Partido Popular) won the elections with an absolute majority, larger than the one the former mayor (María Elena Albentosa) had, while the opposition (Socialist Party) lost some of their popular support. She is the second woman ever to occupy this position.

At the 2015 local elections, the political composition on the local council was:

Party		Seats
	PP	8
	PSOE	7
	IU-Acord Ciutadà	1
	We Want Guardamar del Segura	1

• Torreta de Guardamar, a radio mast. The tallest military structure in the European Union.

• Agrupación Musical de Guardamar del Segura
• guardamardelsegura.com
• Guardamar del Segura Quiz at LetsQuiz