PURPOSE: To produce trichlorosilane at relatively low temperature, by reacting silicon tetrachloride with hydrogen by the use of a catalyst of a metal such as metal of group VIII, chromium, copper, zinc, rhenium, etc., supported on active carbon.

CONSTITUTION: At least one metal selected from one or more metals belonging to group VIII of the periodic table, chromium, copper, zinc and rhenium is supported on active carbon to constitute a catalyst. Active carbon of coconut husk type, charcoal type, petroleum pitch type, etc., may be cited as the active carbon and the active carbon having ≥about 500m2/g specific surface area is preferred. The amount of the catalyst metal supported is preferably 0.05W20 pts.wt. based on 100pts.wt. active carbon. A mixed gas of hydrogen/silicon tetrachloride in a molar ration of 1W200 is passed through a layer filled with the catalyst at about 1W104hr-1 space velocity and reaction is carried out at about 200W700°C at about 0W300kg/cm2/G pressure to synthesize trichlorosilane directly from hydrogen and silicon tetrachloride.