A shielding shell includes a front shell curved from a metal plate and having a base board and two side boards, and a rear shell having a base plate of which a front edge is connected with a rear edge of the base board. Two side plates extend downward from two opposite side edges of the base plate and each is connected with a rear edge of the side board of the front shell by virtue of a strengthening structure. The strengthening structure includes a first strengthening arm extending towards the corresponding side plate from a rear edge of the side board, and a second strengthening arm extending towards the corresponding side board from a front edge of the side plate to be buckled with the first strengthening arm so as to secure the side plate and the corresponding side board together.