Aim\ Studies on sintering action of nanocrystalline powder of W(Cu) by MA(machenical alloying) are presented. Methods\ The pressed samples are sintered in vacuum stove and measured. Results\ It is shown that the grain size is less than 35 nm and the solid solution remains undecomposed after vacuum sintering under the temperature up to 1 000 ℃ and held on 30 min. Conclusion\ W(Cu) solid solution is a stable phase.