An easy-to-tear anti-theft blister packaging box comprises a box body and a box cover. The box body is engaged with the box cover. An outer end edge of the box body is connected with an annular flange. One corner of the flange extends outwardly to form a first tab. An upper portion of 5 the first tab is formed with a notch. One corner of an outer end edge of the box cover extends outwardly to form a second tab in cooperation with the first tab. The outer end edge of the box cover is connected with an easy-to-tear ring through a tear line. An outer end edge of the easy-to-tear ring is closely matched with the flange. One corner of the easy-to-tear ring extends outwardly to form a third tab corresponding in position to the first tab.