The enantioselective addition of allylsilane to an aldehyde is an excellent method to give optically active homoallyl alcohols. Applying this reaction to the asymmetric polymerization of bis(allylsilane) and dialdehyde, the synthesis of a new optically active polymer having chirality on the main chain was possible. Chiral acyloxyborane (CAB) was effective as a catalyst in this asymmetric allylation polymerization.