An enzymatic carbon paste electrode for determination of phenolic compounds is developed. The electrode material was prepared by mixing the monodisperse graphite powder with paraffin and with crude mushroom tissue which contains polyphenol oxidase (PPO) in its living environment. The ratio between components (carbon - tissue - paraffin), was investigated using SCV (Stare Case Voltammetry) techniques in 0.1 M sodium phosphate buffer, pH 7, scan rate 50 mV/s. The derivative voltammogrammes are used to evaluate the biosensor response. The analytical performance was closely related with the carbon powder granulometry. The optimal results regarding the background current and sensitivity (1.57 mA/ppm) were obtained when carbon powder granulometry was 0.09-0.071 mm. It was also studied the activity of the PPO taken from four separated sections of mushroom body. Kinetic of enzymatic reaction resulted according to the Michaels–Menten mechanism. The biosensor response was tested toward different phenolic compounds. The best signal regarding the sensitivity of biosensor (S=2.04 mA/ppm), correlation coefficient (R2= 0.9997) and detection limit (0.7 ppm) was obtained for hydroquinone and the other studied compounds are listed in these order: hydroquinone > catechol > phenol > m-cresol > 4-chlorophenol > p-cresol > 4-nitrophenol > 3-nitrophenol.