A tungsten powder which has tungsten silicide (such as W5Si3) on the surfaces of particles and has a silicon content of 0.05-7% by mass; a positive electrode body for capacitors; an electrolytic capacitor; a method for producing a tungsten powder; and a method for producing a positive electrode body for capacitors. The tungsten powder has an average primary particle diameter of 0.1-1 μm, and tungsten silicide is localized within 50 nm from the surface of each particle.

The tungsten powder contains at least one of tungsten nitride, tungsten carbide and tungsten boride in a part of the surface of each particle. It is preferable for the tungsten powder that the content of phosphorus element is 1-500 ppm by mass, the oxygen content is 0.05-8% by mass, and the content of elements other than tungsten, silicon, nitrogen, carbon, boron, oxygen and phosphorus is 0.1% by mass or less. It is also preferable that the tungsten granulated powder has an average particle diameter of 50-200 μm and a specific surface area of 0.2-20 m2/g. According to the present invention, a tungsten capacitor which has good leakage current (LC) performance can be provided. The present invention relates to: a tungsten powder which has tungsten silicide (such as W5Si3) on the surfaces of particles and has a silicon content of 0.05-7% by mass; a positive electrode body for capacitors; an electrolytic capacitor; a method for producing a tungsten powder; and a method for producing a positive electrode body for capacitors. The tungsten powder has an average primary particle diameter of 0.1-1 μm, and tungsten silicide is localized within 50 nm from the surface of each particle.