B61

B61 may refer to:
 * B61 nuclear bomb
 * B61 (New York City bus) in Brooklyn
 * HLA-B61, an HLA serotype
 * Sicilian, Richter-Rauzer, Encyclopaedia of Chess Openings code
 * Alternative name for the ephrin A1, human gene

B-61 may refer to:
 * B-61 Matador, the first operational surface-to-surface cruise missile built by the United States