Double-layer cylindrical pre-cleaner (type TCQYS) is such a new kind of grain-processing machine with a novel structure, double cylindrical screens and adjustable leaning angle of the sieve. It fills up the deficiencies of low output, bad effectiveness, mono-function and unstable performances of the present pre-cleaning facilities of domestic industries of feed, storage, food and chemical. This kind of pre-cleaner can adjust its leaning angle of screen in its adjustable ranges to regulate the moving speed of the materials in the sieve according to the demanded output and technological effects, effectively separate big impurities like corps stalks, little stones, solid mass etc. and eliminate a proportion of tiny impurities. It is a comprehensive facility, which is able to ensure sub-sequential processing and transporting facilities running well.