A sensitive and selective electrochemical method was developed for the simultaneous determination of dopamine (DA) and paracetamol (PA), based on a multiwalled carbon nanotubes/poly(L-lysine) film modified glassy carbon electrode (MWCNTs/PLL/GCE). The results showed that this new electrochemical sensor exhibited excellent electrocatalytic activity towards the oxidation of the two analytes. Under the optimum conditions, the detection limits were 0.10 mu M for DA and 0.23 mu M for PA. The proposed method has been successfully applied to the simultaneous determination of DA and PA in some real samples.