This utility model relates to a dental floss device which consists of a hollow handle and a hollow extending rod that is connected with the side of the hollow handle and communicated to the hollow handle. The utility model is characterized in that the hollow extending rod is provided with a section of a vertical tubular body at the underside. The tubular hole of the vertical tubular body is communicated to the hollow extending rod and penetrated up to the upper wall surface of the hollow extending rod. The vertical tubular body is provided with a rocking handle pin internally. The rocking handle pin inserts in the vertical tubular body form the upper side of the hollow extending rod. The utility model can thoroughly remove food particles and plaque from the teeth, effectively preventing the oral cavity diseases, such as decayed tooth, periodontitis, ngivitis, and teeth coalition and so on. The utility model is convenient and hygienic to be used and can be repeatedly used.