Waste tire rubber (WTR) powder with different mesh type (60 or 80 mesh) after alkali activation was mixed in wood flour (WF) treated with a compatibilizer, the mixture after oven-dried was gradually filled into thermoplastic high-density polyethylene (HDPE) or polypropylene (PP) base (WTR/WPC) through hot-press molding process.Damping behaviors of HDPE-based and PP-based WTR/WPC strips with 4 different WTR fractions were studied by impulse-agitated testing and half-power bandwidth identification method.Results reveal, WTR incorporation after surface grafting modification has positive on the vibration-reduction behavior of WTR/WPC, and the increment of its loss factor (tanδ) arrives to the maximal value at 10% WTR concentration, with respect to the reference.This mainly attributes to the deformation capacity of elastic but flexible WTR and good interlayer sandwich friction between flexible WTR, rigid WF, and flexible plastic base.Furthermore, the coarse WTR (60 mesh) has more significant effect on the improvement of tanδ of relatively flexible HDPE-based WPC than that of rigid PP-based WPC (69.7% in HDPE base, 61.1% in PP base), especially at relatively low WTR fraction.