The present invention provides a fine silicon powder and the like including fine silicon particles having a microscopically measured particle diameter of 1 μm or more and an average circularity determined in accordance with Formula (1) of 0.93 or more, in which an average particle diameter based on volume, which is measured by a laser diffraction scattering method, is in a range of 0.8 μm or more and 8.0 μm or less, an average particle diameter based on number, which is measured by the laser diffraction scattering method, is in a range of 0.100 μm or more and 0.150 μm or less, and a specific surface area, which is measured by a BET method, is in a range of 4.0 m2/g or more and 10 m2/g or less. Circularity=(4×π×projected area of particle)1/2/peripheral length of particle (1).