This work presents several significant novelties in the field of histamine detection and biosensing through the development of nitrogen and iron co-doped carbon dots (N, Fe@CDs) with intrinsic peroxidase-like activity. The dual-mode sensing mechanism is particularly innovative, simultaneously exploiting both the colorimetric conversion of 2,3,5-triphenyl-2 H-tetrazolium chloride (TTC) to formazan and the fluorescence enhancement of the carbon dots N, Fe@CDs. This approach cleverly integrates enzymatic specificity through porcine diamine oxidase (DAO) with nanozyme catalysis. The ability to achieve both visual detection and fluorometric analysis for precise measurements. The developed dual-mode sensing platform demonstrates excellent analytical performance with both colorimetric and fluorometric detection modes showing linear detection ranges of 1.0–60.0 µM and 0.1–13.0 µM, achieving limits of detection of 0.28 µM and 0.034 µM respectively, with strong linearity (R² >0.9959). The method was successfully applied to determine histamine levels in different fish products, demonstrating excellent accuracy with percentage recovery values ranging from 97.11 to 102.0%. The successful application to diverse fish products demonstrates the practical versatility of this sensing strategy, overcoming matrix interference challenges. This multifunctional nanomaterial-based approach represents a significant advancement in developing cost-effective, user-friendly analytical tools for food quality control and safety assessment.