The invention discloses a 
monocrystalline silicon slicing device capable of freely adjusting size of a 
wafer to be 
cut, and belongs to the technical field of 
monocrystalline silicon. The 
slicing device comprises a working platform, wherein two groups of guide rollers are driven by a 
conveyor belt, a 
chip collecting box is installed in the center of an inner cavity of the working platform, and theend, away from fixing blocks, of a supporting rod is connected with a clamping device; and an electric telescopic rod is arranged in the center of the bottom of a rack, the bottom of the electric telescopic rod is connected with a fixing rod, the outer wall of the fixing rod is uniformly sleeved with sleeves, and 
cutting blades are arranged in the centers of the bottoms of the sleeves. The spacingbetween the sleeves is adjusted in the device, so that the device can 
cut the 
monocrystalline silicon into different sizes; the monocrystalline 
silicon is fixed by the clamping device, so that 
cutting exists in errors caused by the movement of the monocrystalline 
silicon are prevented; and meanwhile, the 
cutting blades rotate, so that blocking blocks rotate like fan blades to generate 
wind force,and chips generated by cutting on the working platform are blown to the 
chip collecting box, and the chips are prevented from splashing onto the monocrystalline 
silicon to damage the surface of the monocrystalline silicon.