Abstract: Y₂O₃film was prepared on the surface of short tungsten fibers by radio frequency magnetron sputtering.The film thickness is about 100 nm.For convenience of study,firstly,the Y₂O₃film was deposited on the tungsten sheets by the same process,and it was heat-treated at 500℃,700℃and 900℃for 1 h,respectively,the surface morphology and phase of the film were analyzed by SEM and XRD,and the heat treatment temperature of short tungsten fiber coated with Y₂O₃film was determined.The results show that the films at 700℃and 900℃are all damaged,while the surface of the film is intact after heat treatment at 500℃,and the crystallinity of the film is improved compared with that of the unheat-treated film.On this basis,the short tungsten fiber coated with Y₂O₃film is heat-treated at 500℃,finally,Y₂O₃film with uniformity,integrity and good crystallinity is prepared on the surface of short tungsten fibers,which can lay a technological foundation for the subsequent preparation of W_f/W composites.