To make straight cuttable a section to be cut by forming an opening between the internal end of a protective section provided in the tip end head section of a handle section and a confronted handle section, exposing a part of a cutting blade being embedded over the handle section and the protective section at the head section, and also, forming a fan shape guide section at a portion opposed to the opening of the head section.

At the tip end of a handle section 5, a head section 6 which is bent into a curved shape is formed, and at the same time, a protective section 7 is formed continuing from the head section 6, and an opening 8 is formed between the internal end of the protective section 7 and the handle section 5 which is confronted with the internal end. Then, a part of a cutting blade is embedded in the head section 6 over the handle section 5 and the protective section 7, and the blade section is exposed at the opening 8. Also, a guide section 10 which expands into a fan shape from the cutting blade 9 side is formed on both surfaces of the head section 6 between the handle section 5 and the protective section 7, being confronted with the opening 8. At the time of usage, the cutting blade 9 is placed at an opening end section of a paper pack by holding the handle section 5, and the cutter is pulled forward, and a cutting surface of the pack is guided by the guide section 10, and thus, the pack is straight cut.