An air vent structure may include spacers mounted at sides of an outlet of an air duct; a single horizontal wing, and an upper and lower horizontal wings that have hinge grooves to which hinge pins of the spacer are inserted and formed in front side portions of the horizontal wings and positioned in horizontally in the outlet, the upper and lower horizontal wings being disposed above and below the single horizontal wing; a main link having a front end portion which a first hinge end portion hinged to a rear portion of both side surfaces of the respective horizontal wings and a rear end portion in which a second hinge end portion is formed at upper and lower portions in the rear end portion; an auxiliary wing connected to the slot of the spacer and the second hinge end portion of the main link; and a dummy wing covering the spacer.