Riba is an Arabic word meaning usury.
Riba or RIBA may also refer to:
- Riba (surname)
- La Riba, a municipality in Catalonia, north-eastern Spain
- Royal Institute of British Architects
- Recombinant ImmunoBlot Assay, a technique used in immunogenetics to detect specific proteins in a sample of tissue. It is also known as the Western Blot test
- Rabbi Isaac ben Asher ha-Levi an 11th century German Tosafist
