1,4-Bis(diphenylphosphino)butane (dppb) is an organophosphorus compound with the formula (Ph<sub>2</sub>PCH<sub>2</sub>CH<sub>2</sub>)<sub>2</sub>. It is less commonly used in coordination chemistry than other diphosphine ligands such as dppe. It is a white solid that is soluble in organic solvents.
Nickel complexes in which the ligand is bidentate or monodentate are known. Palladium complexes containing dppb are used in a variety of catalytic reactions. The ligand's natural bite angle is 94ð in its bidentate coordination mode.