The utilization of 5‐hydroxymethyl furfural (HMF) as a renewable feedstock for polymer synthesis has not yet been achieved as it is structurally asymmetric and contains three active functional groups. Reported here is the unprecedented step‐growth copolymerization of HMF and dihydrosilanes, through a coordination mechanism, to afford linear poly(silyl ether)s in the presence of B(C6F5)3 and the heteroscorpionate zinc hydride complex LZnH [L=(MePz)2CP(Ph)2NPh, MePz=3,5‐dimethylpyrazolyl]. The adduct B(C6F5)3⋅⋅⋅H⋅⋅⋅Zn, confirmed by NMR spectroscopy and DFT calculations, plays a key role in the synergistic catalysis, where B(C6F5)3 activates ZnH and stabilizes the Zn+ active species, and the sterically bulky ZnH effectively inhibits (C6F5)3B from reacting with dihydrosilane to form (C6F5)3B‐H‐Si, which facilely initiates ring opening of furan. The mechanism was studied by DFT simulations.