Plants respond to heavy metal toxicity in a variety of different ways such as immobilization, exclusion, chelation and compartmentalization of the metal ions, and the expression of more general stress response mechanisms e.g. ethylene and stress peptides. One of the most studied plant stress peptides are phytochelatins participating in the detoxification of heavy metals. The synthesis of phytochelatins is catalyzed by phytochelatin synthase (PCS). The possible way of the study of PCS activity in the plant cell exposed by heavy metal is determination of increasing phytochelatins concentration. The main aim of the present work was to suggest a new tool (high performance liquid chromatography coupled with twelve channel electrochemical detector) for the determination of the phytochelatin synthase activity.