Aim. Heavy metal ion pollution is a worldwide problem that causes irreparable damage to humans and other organisms. The traditional detection methods, while accurate, are expensive, complex, and slow, making them impractical for continuous real-time monitoring. Biosensors, however, offer a promising solution with their affordability, ease of use, sensitivity, portability, and on-site monitoring capabilities, effectively addressing heavy metal ion pollution challenges. Conclusions. A new flow injection biosensor system for real time determination of heavy metal ions for water monitoring was developed. Optimal parameters for continuous flow analysis were determined and its main analytical characteristics were investigated, including sensitivity, detection limit, signal reproducibility, and reactivation after inhibition. The developed biosensor system can potentially be used for the analysis of heavy metals in water.