This study fabricated a novel low-cobalt high-entropy alloy (HEA) coating via a cable-type wire feeding laser cladding process, aiming to provide a high-performance and cost-effective alternative for high-temperature valve sealing materials. The tribological properties of the HEA coating, as-cast HEA, and conventional Stellite6 alloy were systematically investigated under 800 °C conditions, accompanied by comprehensive analyses of their microstructural evolution, oxidation behavior, and wear mechanisms. Results reveal that the HEA coating consists of a grain boundary ligament microstructure (the hard BCC grains are enveloped and interconnected by a continuous FCC soft phase), exhibiting a significantly higher microhardness than both Stellite6 Coating and the as-cast HEA, with increases of 22 % and 15 %, respectively, while also demonstrating enhanced toughness. At 800 °C, the HEA coating demonstrates superior tribological performance with a stable friction coefficient of approximately 0.33 and a specific wear rate of 2.52 × 10 −6 mm 3/Nm, representing merely 20 % of Stellite6's wear rate. Comparative analysis indicates that the Stellite6 coating suffers from porous oxide layers prone to spallation, leading to severe material loss. In contrast, the HEA coating forms a dense composite oxide film comprising Al 2O 3 and Cr 2O 3, which effectively isolates direct contact between tribo-pairs and facilitates self-lubrication. Notably, the cobalt content reduction achieves 70 % cost savings while simultaneously improving mechanical performance. This work demonstrates that the developed HEA coating exhibits exceptional wear resistance and self-lubricating capability under extreme thermal conditions, establishing its potential as a high-performance substitute for conventional Stellite6 coatings. These findings provide a new pathway for technological advancement in high-temperature valve sealing materials.