An antenna device for use with a wireless signal processing interface includes a main body; an antenna module received by the main body and having a first signal-receiving bar and a second signal-receiving bar pivotally protruding from a first surface and a second surface of the main body, respectively; and a securing member having a first portion coupled to the main body and a second portion to be detachably coupled to a supporting object. The securing member is made of an elastic material and distorted when coupled to the supporting object so as to provide a securing force to fix the antenna device onto the supporting object.