To provide a dust collector capable of achieving high dust collection efficiency at the bottom face side of a cutting material although dust collection has been conventionally insufficient at the bottom face side of the cutting material and high operability by being arranged to be detachable and re-attachable from/to a portable cutter which enables a user to be moved in the cut traveling direction in a riding state to the cutting material for cutting work.

The dust collector is constituted so that a U-shaped support arm 22 is detachable and re-attachable from/to a base 2 and a box-like dust receiver 21 is supported below a cutting edge 5 through the support arm 22. The dust receiver 21 receives dust generated at the bottom face side of the cutting material for dust collection.