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The superfine pure tungsten powder with a BET particle size of 0.21 μm was prepared by sol spray drying-calcination-hydrogen reduction process, and then it was treated by ball-milling activation. The changes of the morphology as well as other performance characteristics of the superfine pure tungsten powder with the increasing of ball-milling time were investigated, the sintering densification technologies of the as-received powder, the powders ball-milled for 5 h and 10 h, respectively, were explored. Additionally, the rules of properties changes such as the microstructure morphology, the grain size and the microhardness of the pure tungsten sintered body with sintering temperature and ball-milling time were studied in detail. Results show that the ball-milling treatment plays a great activation role in sintering of the superfine pure tungsten powder. When the green compact prepared by the powder milled for 10 h is sintered at 1900 °C for 2 h, the relative density of the sintered compact can reach 97.3%, the sinter temperature reduces by more 600 °C compared to that required for sintering the traditional micro scale powder compact. At the same time, ball-milling treatment can reduce the onset sintering temperature as well as recrystallization temperature substantially, so the sintered tungsten compact with much uniformer and finer microstructure and much better mechanical properties (hardness) can be obtained.