OLB may stand for:

• Oh Lord Buddha - Quotes related to Buddhism
• Olbia - Costa Smeralda Airport, IATA airport code
• Outside linebacker, a defensive position in American and Canadian football
• Object Language Bindings (SQL/OLB) - a standard for embedding SQL in Java
• Oldenburgische Landesbank - a German bank
• Online Bible
• Overpass Light Brigade - Series of illuminated (LED) signs used by activists and others. Each letter is held by a different person.

• Official Log Book

• Athletics at the 2003 All-Africa Games – Women's 100 metres
• Athletics at the 2003 All-Africa Games – Women's 1500 metres
• Athletics at the 2003 All-Africa Games – Women's 200 metres
• Athletics at the 2003 All-Africa Games – Women's 400 metres
• Athletics at the 2003 All-Africa Games – Women's 5000 metres
• Athletics at the 2003 All-Africa Games – Women's 800 metres
• Athletics at the 2003 All-Africa Games – Women's discus throw
• Athletics at the 2003 All-Africa Games – Women's hammer throw
• Athletics at the 2003 All-Africa Games – Women's heptathlon
• Athletics at the 2003 All-Africa Games – Women's high jump
• Athletics at the 2003 All-Africa Games – Women's javelin throw
• Athletics at the 2003 All-Africa Games – Women's long jump
• Athletics at the 2003 All-Africa Games – Women's marathon
• Athletics at the 2003 All-Africa Games – Women's pole vault
• Athletics at the 2003 All-Africa Games – Women's shot put
• Athletics at the 2003 All-Africa Games – Women's triple jump
• Athletics at the 2003 European Youth Summer Olympic Festival
• Athletics at the 2003 Games of the Small States of Europe
• Athletics at the 2003 Pan American Games - Men's marathon
• Athletics at the 2003 Pan American Games - Women's marathon
• Athletics at the 2003 Pan American Games – Men's 10000 metres
• Athletics at the 2003 Pan American Games – Men's Marathon
• Athletics at the 2003 Pan American Games – Women's 10000 metres
• Athletics at the 2003 Pan American Games – Women's Marathon
• Athletics at the 2003 Southeast Asian Games – Men's 5000 metres