Abstract Monitoring of biomarkers can be used to early diagnosis of diseases. Changes in levels of cysteine can indicate several disorders, because of this, development of suitable sensors are essential to welfare of people. Herein it was described the electrochemical response of a hybrid system modified electrode composed by gold nanoparticles and manganese meso-tetra(pentafluorophenyl) porphyrin for the sensing of cysteine. For this purpose, fluorine tin oxide-coated glass (FTO) electrodes were chosen as substrate due to their low cost and easily modifying surface. The hybrid system was deposited on the FTO surface using a self-assembly strategy and all experiments were performed at pH 7.0. The obtained modified electrode has shown good response for cysteine oxidation in amperometric studies with figures of merit comparable to other sensors described in literature.