Abstract: A band holder is provided. The band holder includes: a holding unit having a holding unit body; a rotating unit including an arm pivotally connected to the holding unit body and a fixed hanging portion disposed at the arm pivotal end, wherein the rotating unit is rotated and fixed in place relative to the holding unit; and a spacing adjustment mechanism disposed at the arm and having a movable hanging portion, the movable hanging portion undergoing linear displacement in a lengthwise direction of the arm and being positioned, so as to adjust its distance from the fixed hanging portion. Therefore, not only is a mask comfortable to wear, but the human head and ear also perceive no sense of compression.

Abstract: A mask structure includes a mask body having at least one edge side; at least one subsidiary part connecting with and corresponding to the edge side, wherein an angle is formed between the subsidiary part and the mask body; and a band set fixing at the two sides of the mask body.