聚丙烯腈基炭纤维和废弃聚乙烯作为改性剂，采用热熔共混、絮凝处理、熔融共挤3种工艺对道路沥青进行改性，并研究了炭纤维分散性对沥青性能的影响。研究表明：炭纤维和废弃聚乙烯对沥青的改性为物理改性，随着炭纤维含量的增加，改性沥青的软化点和延度上升，针入度降低，改性沥青高温性能得到改善。过高的炭纤维含量将不利于分散而发生纤维团聚，当炭纤维含量超过0.1%，将造成改性沥青性能降低。微观观察发现，熔融共挤工艺较其他工艺，炭纤维与聚乙烯能较好的分散和结合，使得聚乙烯与炭纤维形成良好的类荆棘状吸附，在沥青中分散最佳，改性沥青的高温性和抗车辙性能得到较大提高。“,”Recycled waste packaging polyethylene ( WPE) and chopped polyacrylonitrile-based carbon fibers ( PAN-CFs) were dispersed in molten asphalt at 170℃ with a shearing machine at 3 800 r/min for 60 min to modify its properties to meet the demands of motorway paving. WPE and PAN-CFs were mixed by three methods before the dispersion:( a) simple blending, ( b) first dis-solving WPE in xylene, then mixing and evaporating and (c) blending and extrusion to rods of 1mm diameterat 170 ℃ which were fed directly into the hot asphalt. The PAN-CF content was varied in the range 0 to 0. 12 wt% while the WPE content was constant (4 wt%). Results indicate that WPE and PAN-CFs are dispersed in asphalt to form a network structure by the xylene-assisted mix-ing or blending-extrusion methods. The softening points, penetration degree and ductility are improved with increasing content of PAN-CFs up to 0. 1 wt%. Aggregation of the two modifiers occurs beyond 0. 12 wt% of PAN-CFs, which degrades the properties of the modified asphalts. A fiber length of 5 mm is optimum for their best dispersion in the asphalt. Segregation of the modifiers from the modified asphalts can be prevented by increasing the content of PAN-CFs. The blending-extrusion method is best to form a fine network structure, which achieves a best performance. A model is proposed to explain the observed dispersion behavior in as-phalt.