A clamping apparatus for an antenna includes: an arm unit coupled to a support pole and extending in one horizontal direction from the support pole by a predetermined distance; a common coupling unit detachably mounted to a front end of the arm unit by insertion and detachment operations of a coupling shaft elongated vertically, the common coupling unit being selectively rotatable from side to side about the coupling shaft; a rotation unit having a front end detachably mounted to a front end of the coupling unit by insertion and detachment operations of a rotary shaft elongated vertically, the rotation unit being rotatable from side to side by a predetermined angle about the rotary shaft; and a tilting unit coupled to the front end of the rotation unit to be tiltable vertically, an antenna device being coupled to the tilting unit.