Methandiides, bisylides, and yldiides are geminal dianions having two lone pairs of electrons at the central carbon atom and are applicable to construct f-block carbon multiple-bond complexes. However, cerium yldiide complexes possessing a cerium–carbon double bond are not known to date. Herein we report cerium yldiide complex 4 which bears a short Ce–C bond of 2.461(5) Å, exhibiting significant cerium–carbon multiple-bond character. The nature of the Ce–Cmethine bond in 4 was probed by DFT, unveiling a rare Ce←←[jls-end-space/]C double dative bond. Therefore, 4 is the first cerium yldiide double-bond complex. Complex 4 underwent nucleophilic addition toward ClBPh2 to give 5 incorporating a borate-functionalized ylide. These findings may provide straightforward access to lanthanide yldiide multiple-bond complexes from lanthanide ortho-metalated ylides.