Smartphone holding device

The present invention relates to a smartphone holding device and, more specifically, to a smartphone holding device capable of supporting a smartphone, comprising: a main body which is formed so as to be detachable from an edge of the smartphone, has a cut part formed by cutting each corner thereof, and has a support groove that is adjacent to the cut part and is formed on a rear surface direction of the smartphone; and a finger insertion part which is elastically coupled to the cut part of the main body, can be spaced in a horizontal direction such that a finger can be inserted therein , and has a support protrusion that can be inserted into and fixed to the support groove of the main body after rotating by a predetermined angle towards the rear surface of the smartphone so as to support the smartphone, and thus the smartphone holding device has a sliding prevention function and a holding function.