Mechanical milling can easily obtain nanopowders and consolidate milled powders to full density. Milling time exerts a critical influence on the performance of powders and bulk materials. In this study, the tungsten (W) combined with niobium (Nb) powder was wet milled for 15, 25, 36, and 45 h, and consolidated by spark plasma sintering. The W-Nb specimens were irradiated with 9.90 × 10₂₄Sions/m₂ helium (He) beams for 11 min. The solid solution degree of W and Nb influences the irradiation damage of the specimen. The surface damage of specimen milled for 36 h which has the lowest solid solution degree is the most serious among all specimens, such that the nanostructure “fuzz” is formed only in the said specimen. In the same specimen, tungsten presents different surface damage degrees owing to its different orientations. After characterization, the W-Nb specimens were isochronally annealed at 900, 1100, and 1300 °C for 1 h. The grains grow in Nb but barely change in W. Nb exerts a strong influence on the right shifting of He desorption peaks.