The invention provides application of a 
diffusion barrier material, a high-temperature 
coating and a preparation method and application thereof, and a gas 
turbine hot end part, and belongs to the technical field of high-temperature protective coatings. The components of the 
diffusion barrier material include MeSi2, and Me includes Cr or Mo. The 
diffusion barrier material is compact in 
crystal structure and good in high-temperature-oxidation-resistant property, and has good 
thermal expansion compatibility with a base material; the high-temperature 
coating comprises an outer layer and an inner layer with the 
diffusion barrier material; the high-temperature 
coating can inhibit mutual diffusion of 
alloy components between a base body and the coating, the high-temperature-oxidation-resistant capacity of the coating is improved, meanwhile the situation that the 
mechanical property of the base body is lowered due to mutual diffusion is avoided, and the service life of parts is prolonged; andthe preparation method of the high-temperature coating is mature and reliable and good in 
repeatability, and large-area industrial production is easy to implement; and both the 
diffusion barrier material and the high-temperature coating can be used for 
machining the gas 
turbine hot end part, and the gas 
turbine hot end part containing the 
diffusion barrier material or the high-temperature coatinghas the long service life and high working reliability.