PVC-based damping materials are prepared with polyvinyl chloride (PVC) as matrix, dioctyl terephthalate (DOTP) as plasticizer, inorganic CaCO3 as filler, calcium and zinc as heat stabilizer, OP-10 as emulsifier and liquid paraffin as lubricant. Then properties and morphology of the sample were characterized by using DHR, DMA, SEM etc. The orthogonal design was used to explore the influence of each component on the performance. The results show that the ratio of filler CaCO3 and plasticizer DOTP has the most significant effect on its damping performance. When the raito of PVC: CaCO3: DOTP: OP-10 is 45: 33: 22: 2, and the frequency is within the range of 0.01～150 Hz at 25℃, tan δ maximum value increases from 0.497 to 0.604;the apparent viscosity at a shear rate of 0.1 s-1 is 3738 Pa·s, and at a shear rate of 150 s-1 is 2.19 Pa·s, which shows that the sample has excellent sag resistance and stability. The micro-aggregation model was constructed through LASD morphology analysis, and the mechanism of the agglomeration-de-agglomeration of rigid fillers and the deformation of polymer microspheres on rheological properties was proposed, which provided technical ideas and theoretical foundations for the continuous research of LASD.