ABSTRACT Laccase is a copper-containing oxidase that catalyzes reduction of molecular oxygen to water and the oxidation of a phenolic compound. In this paper, laccase was utilized to synthesize 4,4’-Biphenyldiamine using p -chloroaniline as substrate by means of a coupling reaction. The synthesized compound, 4,4’-Biphenyldiamine, presented low antifungal activity against the phytopathogenic fungus Botrytis cinerea , however the antioxidant ability, measurement by ORAC-PGR method, was higher than substrate.This work corresponds to the first report of synthesis 4,4’-Biphenyldiamine, from p -chloroaniline in a lacasse-catalyzed reaction. Keywords: p -chloroaniline, 4,4’-Biphenyldiamine, laccase, antioxidant activity, antifungal activity. e-mail: leonora.mendoza@usach.cl, milena.cotoras@usach.cl 1. INTRODUCTION Laccases (benzenediol: oxygen oxidoreductase, EC 1.10.3.2) are copper-containing oxidases that catalyze the single-electron oxidation of a wide range of phenolic compounds and reduction of molecular oxygen to water