Abstract: A method for preparing tantalum-tungsten alloy powder includes the following steps: providing a tantalum-tungsten alloy ingot; repeatedly smelting the tantalum-tungsten alloy ingot; forging a product of the previous step; placing the product of the previous step in a hydrogen atmosphere to perform a hydrogenation heat treatment; mechanically crushing the product of the previous step to obtain a coarse powder; sieving, from the coarse powder, a powder having a particle size ranging from a ?m to b ?m, wherein a=10-20 and b=50-60; performing dehydrogenation heat treatment on the product of the previous step under vacuum; adding a magnesium powder to the product of the previous step to perform a deoxygenation heat treatment; and performing plasma spheroidization treatment on the product of the previous step such that the sphericity of the powder reaches more than 99%.