B70 or B-70 may refer to:

• B70 (chess opening), a code for the Dragon Variation from the Encyclopaedia of Chess Openings
• B70 (New York City bus), a public transit line in Brooklyn in New York City
• B-70 Valkyrie, a planned American supersonic bomber aircraft
• Bundesstraße 70, a federal highway in Germany
• CD86, a human protein also called B70
• HLA-B70, an HLA-B serotype
• West Bromwich, UK postcode
• The pennant number assigned to Turkish battlecruiser TCG Yavuz Sultan Selim
• Bestune B70, a sedan