The invention relates to the technical field of moulds and particularly relates to an extruding module with adjustable inner width. The mould comprises a mould body which comprises an extruding mould plate, a transition mould plate positioned at the upper end of the extruding mould plate, a first supporting plate positioned at the upper end of the transition mould plate, a second supporting plate positioned at the upper end of the first supporting plate, a first bus plate positioned at the upper end of the second supporting plate, a second bus plate positioned at the upper end of the first bus plate and a forming mould plate positioned at the upper end of the second bus plate. According to the extruding module with adjustable inner width provided by the invention, connecting plates are controlled to transversely translate through adjusting screws in inner threaded holes on two sides, so that transversely moving sliding plates fixedly connected to the connecting plates are controlled to translate inside the extruding runners; the transversely moving sliding plates maintain the sealing property of the extruding runners by being connected to the flexible connecting plates at the lower ends, so that hot molten plastic is conveniently imported to avoid waste; the inner structure is simple and convenient to adjust, and the extruding mould is steady in structure and convenient to assemble and disassemble, and the production efficiency is greatly enhanced.