A method, medium, and system rendering 3-dimensional (3D) graphic data. The method of rendering 3D graphic data may include grouping objects from among transparent objects included in graphic data, which overlap each other in a 3D space, and rendering the group and remaining objects excluding the grouped objects, in an order determined according to the distance between the group and a viewpoint and the distance between the remaining objects and the viewpoint. In particular, in the rendering of the group, the objects included in the group may be rendered in an order determined according to the distance between each unit element of each object belonging to the group and the viewpoint. By using such a method, medium, and system, rendering picture quality of a transparent object may be improved by avoiding rendering errors.