The title compound, [ZrW(C 5H 5) 2(C 2H 3O)Cl(CO) 5] or [W(CO) 5C(CH 3)OZr(C 5H 5) 2Cl], consists of two metal centres, with a (tungsten pentacarbonyl)oxymethylcarbene group coordinating as a monodentate ligand to the chloridozirconocene. The two halves of the molecule are related by a crystallographic mirror plane. Delocalization through the Zr—O—C=W unit is indicated by a short Zr—O distance and a nearly linear Zr—O—C angle.