Phenolic compounds are among the major classes of pollutants produced by industrial and agricultural activities. The amperometric biosensors have been mainly applied to the determination of phenolic compounds because of the advantages such as good selectivity, low cost, and easy automation. Amperometry is a method to measure the electric current that flows as a result of reactions generated at the electrode. Amperometric phenol biosensors are most often based on tyrosinase, laccase or horseradish peroxidase immobilized on the electrode surface. The immobilization of enzymes into ordered thin materials has attracted considerable attention over the past few years. The present researches have demonstrated that biomolecules immobilized in different matrixes retain their functional characteristics to a large extent. These new materials are of great interest for applications as biosensors and biocatalysts. Lately, also conducting polymers have attracted much interest in the development of biological sensors. The electrically conducting polymers are known as possessing many interesting features, which allow them to act as excellent materials for immobilization of biomolecules.