To provide a folding blade cutter capable of cutting paper of any varying thickness by a single sheet or plural sheets as desired without the fear that the cutter might injure a soft rule or might be deviated from the rule to cut the paper to the undesired shape.

A cutting guide 4 is provided from almost the tip of the cutting blade 3 of a folding blade cutter 1 up to a spot remote from the tip by a specified distance in such a manner that the blade tip is envelopped by the guide 4. In addition, regulatory members 5, 7,8, 10 for controlling the jutting amount of the blade 3 from this guide 4 are provided. It is also possible to control the jutting amount of the blade depending on only the blade retracting mechanism of the folding blade cutter main body.