The use of [CuDipyCl2] as a biomimetic catalyst in the construction of an amperometric enzymeless biosensor for phenol determinations is reported. The sensor was prepared modifying a glassy carbon electrode with a Nafion® membrane doped with [CuDipyCl2]. The sensor presented a higher response for dopamine in 0.1 mol l-1 phosphate buffer at pH 7, with an applied potential of -50 mV versus SCE. With the optimized operational conditions a linear response range between 4.0×10-5 and 6.0×10-4 mol l-1, with a sensitivity of 350±10 nA l mmol-1 cm-2 and a detection limit of 9.0×10-6 mol l-1 were observed for the sensor. The response time presented for this sensor was approximately 1 s, presenting the same response for at least 50 measurements, with good repeatability (R.S.D. 3.8%, for n=9). The difference of the response between four preparations was 7%. Detailed investigations of the sensor response for monophenol and diphenol compounds and interfering species were carried out. © 2002 Elsevier Science B.V. All rights reserved.