Abstract The crystal structure of bis{(di-i-butyldithiophosphinato)gold(I)}, {AuS2P(i-C4H9)2}2, has been determined at 223 K. The white needles are triclinic, space group P[unk], with unit-cell dimensions of a = 8.0238(5) Å, b = 8.9747(6) Å, c = 9.99655(7) Å, α = 64.965(1)°, β = 79.732(1)°, γ = 73.263(1)°, Z = 2, and D x = 2.172 g/cm3. The structure was solved using direct methods and refined by a full-matrix least-squares procedure to a final R(F) = 0.0278 and Rw(F 2) = 0.0638 using 2787 reflections. Bis{(di-i-butyldithiophosphinato)gold(I)} has a dimeric structure with bridging dithiophosphinate ligands and is essentially linear with an intramolecular Au···Au distance of 3.17 Å and no intermolecular interactions.