In this paper,the characteristics of flexural vibration suppression of a beam using rotational dynamic vibration absorbers are studied. Vibration equations of the beam carrying rotational dynamic vibration absorbers are established using the spectral element method. Then the influences of the installation location,the moment of inertia of the rotational dynamic vibration absorber on the wide band vibration attenuation are analyzed. The numerical analysis result shows that rotational dynamic vibration absorbers have a good performance of suppressing flexural vibrations of beam structures. A widest vibration reduction bandwidth and a maximum energy absorption capacity can be obtained when the rotational dynamic vibration absorbers are installed on the position of maximum modal angular displacement. The increase of the moment of inertia of the rotational dynamic vibration absorbers can also improves the vibration attenuation performance. Finally,the vibration attenuation effect of the rotational dynamic vibration absorber is verified by the experiment. The experiment result also illustrates the advantages of the rotational dynamic vibration absorber that it can improve the vibration reduction performance without increasing the additional mass.