A spout type fluidized bed reactor for synthesis of organic silicon comprises a reactor body, an expanded section, tube bore-hole type combination distributors, cyclone separator components, a back-to-bed valve, a powder-ridding tank valve and tubular heat exchangers, wherein the tube bore-hole type combination distributor is arranged at the bottom of the reactor bed body and comprises a conical gas distributor, a straight tube pore-type distributor and a spouted gas tube; the tubular heat exchangers are arranged in the reactor bed body, heat exchange carriers flowing through the heat exchanging tubes from bottom to top, to achieve single-tube pass heat transfer, so that the heat transfer between the tube surfaces and reacting fluid is even, and radial and axial temperature difference aresmall; particles separated by the cyclone separating device are directly returned back to the bed by the inner and external cyclone separating devices in time and not be taken out of the bed or partial particles are taken out, thereby reducing the catalyst content in the bed and the temperature fluctuation and being beneficial to improving reaction efficiency.