Aveiro may refer to:
- Aveiro, Pará, a municipality in Brazil
- Aveiro, Portugal, a city and municipality in Portugal
- Região de Aveiro, surrounding the city above
- Aveiro District, surrounding the municipality above
- Roman Catholic Diocese of Aveiro, surrounding the city above
- Aveiro Lagoon (Ria de Aveiro), near the city above
- Aveiro Light, at the entrance to the lagoon above
People
- Dukes of Aveiro, an aristocratic Portuguese title, granted in 1535
- Cristiano Ronaldo dos Santos Aveiro (born 1985), Portuguese footballer
- Kátia Aveiro (born 1977), Portuguese singer
- José Aveiro (1936–2024), Paraguayan footballer