The corrosion of laser marked M340 martensitic stainless steel for biomedical applications was investigated using the scanning vibrating electrode technique (SVET) under simultaneous polarization and cyclic voltammetry in a 0.1 M NaCl solution. The laser marking greatly increases the active dissolution of the affected region and decreases the pitting potential due to Cr loss by volatilization and oxidation on the laser-melted zone. Laser marking also increases cathodic currents on the formed oxide resulting in a higher susceptibility to active dissolution and pitting corrosion. (C) 2016 Elsevier Ltd. All rights reserved.