The polymerization behavior of phenolic azosulfonates and triazene by means of enzymatic polymerization using horseradish peroxidase was studied. While for the latter one, only oligomerization was observed, sodium 4 hydroxybenzenediazosulfonate was successfully homopolymerized. The obtained polymer had an average molecular weight of (M) over bar (n) = 3 000 with a polydispersity index of 1.51. This is the first example of a homopolymer bearing an azosulfonate function in every monomer unit.