The invention relates to a technique and an apparatus for producing a packing piece of a packing box which is made of paper composite material and is used for storing foods for a long time in asepsis. In the prior art, the packing piece of the packing box is produced by performing impressing, cross cutting into uniwafers, cutting edges and sealing on the composite and printed wound roll packing material. The prior art needs a plurality of apparatuses for cooperation. The invention aims to provide a technique and an apparatus for producing the packing piece of the packing box. The technique comprises that: the packing material is wound, the axial position is corrected automatically by rectifying a deviation, printing marks are aligned, the indentation line is pressed, a sealing film is adhered, the product enters processes of vertically sealing, hot adhering and press fit after preformation to finish the vertical sealing to produce a paper pipe; the vertical sealing position of the paper pipe is cooled, the paper pipe is pressed flat left and right along the indentation line and is positioned and cut, and the packing piece of a packing box is produced by automatic calibration and collected into a pile. The invention has the advantages that one apparatus finishes the whole production technique, the working procedure is simplified, the number of fault points is small, the rate of finished product is high, the production efficiency is high, the product quality is stable, the production cost is low, and the invention is suitable for large-scale industrial production.