Long-term exposure to the highly toxic heavy metal arsenic can harm ecological systems and pose serious health risks to humans. Arsenic pollutant in water and the food chain must be addressed, and active prompt detection of As(III) is essential. The development of an effective detection method for As(III) ions is urgently needed to slow the alarming growth of arsenic pollution in the environment and safeguard the well-being of future generations. This study presents the results of our exhaustive investigation into cubic CsPbBr<inf>3</inf> single crystals, the glassy carbon (GC) electrode modification with CsPbBr<inf>3</inf> single crystals prepared by direct solvent evaporation, as well as our observations of the material's remarkable electrocatalytic properties and exceptional anti-interference sensing of As(III) ions in neutral pH media. The developed CsPbBr<inf>3</inf>/GC is exceptionally useful for the ultra-sensitive and specific identification of arsenic in water, exhibiting a detection limit of 0.381 μmol/L, a rapid response across a defined range of 0.1–25 μmol/L, and an ultra-sensitivity of 0.296 μA/μmolL−1. CsPbBr<inf>3</inf>/GCE (prepared without a specific reagent) is superior to other modified electrodes used as sensors in electrocatalytic activity, detection limit, analytical sensitivity, and stability response. © 2023 Elsevier B.V., All rights reserved.