A heterobimetallic complex with the first unspported bond between an actinide and a group 13 elements, (CpSiMe3)(3)U-AlCp star (Cp-star=C5Me5) (1), was synthesized by reaction of (CpSiMe3)(3)U and 1/4((CpAl)-Al-star)(4) in toluene. Density functional theory calculations indicate that the U-Al bond exhibits some covalent character resulting from a (CpAl)-Al-star -> U charge-transfer.