The preparation is reported of two series of oligo(oxyethylene) methacrylates containing residues of 2,4-D and CMPA herbicides covalently bound via an ester bond to oligoether side groups having different degree of oligomerization (DPn = 2, 4, 8). The two series of monomers, when submitted to free radical polymerization gave the corresponding homopolymers, that exhibited a water uptake generally lower than 50%. A series of linear and crosslinked polymeric herbicides was also prepared by copoly-merization of the CMPA-containing tetraoxyethylene methacrylate with different comonomers, such as dioxyethylene and octaoxyethylene monomethacrylate, acrylamide, methylene bisacrylamide and 4-vinylpyridine. All the synthesized polymeric herbicides were tested for their release properties in aqueous solution buffered at pH 4, 7 and 9. The herbicide release profiles have been discussed in relation to the polymer inherent structural features and compared with the corresponding polymers obtained by 2,4-D and CMPA binding to preformed poly [oligo(oxyethylene) methacrylate]s. In any case the release kinetics do not fit a simple diffusional scheme and they can be reproduced by the contemporary occurrence of two exponential decay processes, differing by three orders of magnitude in their absolute rates