Abstract: A structure of modem shell with round sound suppression comprises: a box formed by opposite upper and lower half shell bodies, wherein a concave spacing the opening of which is directed outwards is installed thereon, while within the spacing is installed with a line output hole; a covering plate the size of which is enough to cover the opening of the spacing, and a plurality of through holes is installed on the covering surface thereof; and a buckling mechanism is formed by at least two pairs of buckling holes and a pillar; thereby, the spacing is used to locate a trumpet and then is covered by a covering plate so to effectively suppress the round sound generated by the modem.