| Alca | |
| Native Name Lang: | es |
| Settlement Type: | District |
| Mapsize: | frameless |
| Subdivision Type: | Country |
| Subdivision Name: |  Peru |
| Subdivision Type1: | Region |
| Subdivision Name1: | Arequipa |
| Subdivision Type2: | Province |
| Subdivision Name2: | La Unión |
| Parts Type: | Subdivisions |
| Parts Style: | para |
| Established Title: | Founded |
| Established Date: | May 4, 1835 |
| Seat Type: | Capital |
| Seat: | Alca |
| Leader Title: | Mayor |
| Leader Name: | Benjamin Barrios Bellido |
| Unit Pref: | Metric |
| Area Total Km2: | 193.42 |
| Elevation M: | 2750 |
| Population Total: | 2263 |
| Population As Of: | 2005 census |
| Population Density Km2: | auto |
| Timezone1: | PET |
| Utc Offset1: | -5 |
| Blank Name Sec1: | UBIGEO |
| Blank Info Sec1: | 040802 |
Alca District is one of eleven districts of the province La Unión in Peru.[1]
The people in the district are mainly indigenous citizens of Quechua descent. Quechua is the language which the majority of the population (78.33%) learnt to speak in childhood, 20.69% of the residents started speaking using the Spanish language (2007 Peru Census).[2]