Abstract: Cr-coated zirconium alloy claddings, as accident-tolerant fuel cladding schemes, have garnered significant attention in the nuclear materials field due to their excellent anti-oxidation performance, low thermal neutron absorption cross-section, and superior thermomechanical properties. This study focuses on the CPR1000 nuclear power unit, replacing all fuel claddings with Cr-coated zirconium alloys to systematically assess the impact of Cr coatings on activated corrosion products in the primary circuit. Through numerical simulation methods, this research thoroughly analyzes the deposition characteristics of radioactive nuclides in steam generators, main pipelines, and reactor cores. The study results reveal that the corrosion release of Cr coatings has a greater influence on the activated corrosion products inside the reactor compared to outside. Importantly, the application of Cr coatings does not alter the dominant position of ⁶⁰Co, this indicates that their impact on existing reactor operation modes is manageable. Such findings provide crucial theoretical and data-based support for the practical application of Cr-coated zirconium alloy claddings in nuclear power plants.