Highway, especially expressway plays a very important role in economic development of today. To deal with the traffic load, the surface of expressway should have the nature of strength, load-bearing ability, skid-resistance, free of penetration and duration. AC is one of the high type pavements. With the rapid development of highway, most of the AC pavement will be destroyed by heavy traffic loads, and should be maintained with millions of waste materials produced. Plant-mixed hot-regenerated AC is to recycle these waste materials, and apply part of them as one of the ingredients of the new AC of the new pavement. Method of mix design of the Plant-mixed hot-regenerated AC is discussed is this article. The method was applied in the maintenance of the Chang-Ying expressway and has obtained relatively obvious economic effect and social effect.