Abstract: A method and the related system for sampling solid materials. Materials as continuously manufactured from a compression molding machine are sampled at fixed intervals and the materials thus sampled are fed into a transport pipe so as to be transferred by being accompanied by a transport plug into an inspecting station at low speed from its stand-by position in the pipe when a gas control means is set in a feed mode. After transferring sampled materials the transport plug left at its terminal position in the transport pipe is automatically returned to the stand-by position through the transport pipe when the gas control means is set in a suction mode. By executing the above steps repeatedly, sampled materials are successively transferred into the inspecting station by being accompanied by the transport plug under unmanned operation.