Four phenol derivatives (m-cresol, 3-methylcatechol, 4-methylcatechol, and 4-ethylcatechol) were polymerized using the horseradish peroxidase reaction, and their metal adsorption capabilities were studied. Fourier transform infrared (FF-IR) spectrometry and size-exclusion chromatography indicated that the phenol monomers polymerized to give polyphenols having molecular weights from 700 to 3000. During metal adsorption studies, poly(3-methylcatechol) adsorbed copper ions at 100% in a solution of pH 5.0, whereas poly(m-cresol) failed to adsorb any copper ions. Gold ions selectively adsorbed to poly(4-ethylcatechol) in acid media and formed gold particles via reduction of the polyphenol.