| Daya Vieja | |
| Settlement Type: | Municipality |
| Pushpin Map: | Spain |
| Pushpin Map Caption: | Location in Spain |
| Subdivision Type: | Country |
| Subdivision Name: |  Spain |
| Subdivision Type1: | Autonomous community |
| Subdivision Type2: | Province |
| Subdivision Name2: | Alicante |
| Subdivision Type3: | Comarca |
| Subdivision Name3: | Vega Baja del Segura |
| Subdivision Type4: | Judicial district |
| Subdivision Name4: | Orihuela |
| Coordinates: | 38.1047°N -0.7383°W |
| Elevation M: | 4 |
| Area Total Km2: | 3.1 |
| Population Total: | - |
| Population Demonym: | Dayense |
| Population Density Km2: | auto |
| Blank Name Sec1: | Official language(s) |
| Blank Info Sec1: | Spanish |
| Timezone: | CET |
| Utc Offset: | +1 |
| Timezone Dst: | CEST |
| Utc Offset Dst: | +2 |
| Postal Code Type: | Postal code |
| Postal Code: | 03177 |
| Area Code Type: | Dialing code |
| Leader Title: | Alcalde |
| Leader Name: | José Vicente Fernández Costa (2019) |
| Leader Party: | Compromís |
Daya Vieja (pronounced as /es/) is a municipality of the Valencian Community (Spain), situated in the south-east of the Province of Alicante, in the comarca of Vega Baja del Segura.
Daya Vieja is situated on the western side of the Segura river, one kilometre (0.6 miles) from San Fulgencio. It is connected to Guardamar del Segura, Dolores and Crevillente by a four-lane highway.
It has boundaries with Daya Nueva, Dolores, Formentera del Segura and San Fulgencio.
The area dates back to the 18th century when the Pinohermoso family obtained the land. Until 1707, Daya had been incorporated in Orihuela 'county' and it did not fully lost ties to the city until 1833.
Together with Daya Nueva, it belonged to the Roca de Togores family and was split from Orihuela in 1791. This family sold local farming land in 1928 for 1,500,000 pesetas (€9,000) to the García Palmer and García Castillo brothers, who divided it before selling it on to smaller proprietors.
The main economic activity in Daya Vieja is farming irrigated fields, using water from channels originating at Alfeitamí, the most frequently found crops are artichokes, hemp, potatoes and corn. Herds of sheep and pigs are also to be found.