To produce a metallic silicon particle having copper silicide on the particle surface by heating a raw metallic silicon particle and a copper chloride particle having a specific average particle diameter at a specific temperature in a nonoxidizing gas atmosphere.

A raw metallic silicon grain having 50μm to 2mm average particle diameter in an amount of 100 pts.wt. is nearly homogeneously mixed with a copper (I) chloride particle and/or a copper (II) chloride particle having ≤1mm average particle diameter and the resultant mixture is then heated at ≥250°C temperature in a nonoxidizing gas atmosphere such as nitrogen, hydrogen, Ar or a mixed gas thereof. Thereby, a metallic silicon particle having copper silicide on at least the particle surface is obtained. The resultant particle is used as a catalyst capable of carrying out the reduction with hydrogen at a high efficiency without causing the clogging of a charging line or deterioration in a fluidized state even in a fluidized bed reaction for reducing chlorosilanes with hydrogen and producing hydrogenated chlorosilanes.