Co-condensation of cobalt atoms with an excess of (E,E)-1,4-bis(trimethylsilyl)buta-1,3-diene in hexane at -196°C yields the homoleptic bis(butadiene) complex [Co{η-C4H4(SiMe3)2}2] (1) as the sole volatile product. Compound 1 was characterized by 1H NMR and EPR spectroscopy, mass spectrometry and a single-crystal X-ray structure determination.