Accident tolerant fuel can enhance the fuel reliability of active cooling in a reactor core for a longer time period during design-basis and beyond-design-basis accidents as well as maintain or improve the fuel performance during normal and transient operation. This study focuses on the coated cladding concept, which was selected after thorough consideration of the various performances by nuclear reactors during accidents and normal operation. In the coated cladding concepts, the combination of coating material and coating method is a crucial factor in determining the cladding performance. As a new coating material, a chromium-aluminum (Cr-Al) alloy was developed to increase corrosion resistance during normal operation and oxidation resistance during accidents. The Cr-Al alloy showed a superior oxidation resistance compared to Zircaloy-4 cladding in a high-temperature oxidation test up to 1,400°C, and it showed more corrosion resistance than Zircaloy-4 cladding in a 360°C pressurized water reactor-simulated loop condition. Arc ion plating was developed as a coating method to obtain good adhesion of the coated Cr-Al alloy layer on the zirconium (Zr) alloy cladding. After fabricating the coated cladding, test samples were evaluated under normal conditions (corrosion, creep), accident conditions (oxidation, ballooning/rupture), and research reactor conditions (corrosion, stability) using the Halden reactor. The Cr-Al alloy coated Zr cladding samples showed excellent performance under most test conditions, and no severe damage or peeling of the coating layer was observed.