The invention belongs to the field of silicon chemical industry, and relates to a trichlorosilane synthesis furnace. The trichlorosilane synthesis furnace comprises a lower casing and a trapezoidal casing, wherein a gas distribution plate is arranged at the joint of the lower casing and the trapezoidal casing; rotating spray tubes and cylindrical spray tubes are uniformly arranged on the gas distribution plate of the trichlorosilane synthesis furnace and are arranged in a cross manner. According to the trichlorosilane synthesis furnace, two different types of spray tubes are arranged on the gas distribution plate and comprise the rotating spray tubes and the cylindrical spray tubes, the rotating spray tubes and the cylindrical spray tubes are arranged on the gas distribution plate in a cross manner, when hydrogen chloride gas enters a middle casing through the rotating spray tubes and the cylindrical spray tubes and is subjected to a reaction with silica powder, the hydrogen chloride gas sprayed from the rotating spray tubes and the hydrogen chloride gas sprayed from the cylindrical spray tubes interact with each other, so that the silica powder and the hydrogen chloride gas are sufficiently reacted, and further, the silica powder can be effectively prevented from falling on the gas distribution plate by means of spray holes in the rotating spray tubes and oblique spray holes in the cylindrical spray tubes.