To provide a snap hinge device for a folder-type mobile terminal by which users experience an aural feeling of use when opening and closing a folder, and a sense of comfort therefrom.

The snap hinge device includes: a hinge housing; a hinge shaft; an elastic member provided on the hinge shaft; a cam unit including first and second cams which are faced to each other, wherein the first and second cams come into close contact with each other by the elastic member thereby conducting cam action; and a cam cover coupled to the hinge housing to shield the cam unit from the outside of the hinge housing, wherein a prescribed gap (g2) is formed between an outer surface of the hinge shaft and an inner face of the second cam such that the force provided by the elastic member compels the outer surface of the hinge shaft and the inner face of the second cam to strike into each other and generate an aural snap when opening and closing the folder of the mobile terminal.