The old cement concrete pavement has a good recycling value, compared with the ordinary recycling technology, in-situ granulation technology can quickly complete the deep crushing of old cement concrete pavement in place, which is fast and efficient, and has better economic benefits. In order to realize the recycling of the old cement concrete pavement, the properties of in-situ granulated recycled aggregate are researched in this study, factory recycled aggregate and natural aggregate through the method of crushing regeneration, and carried out mechanical properties test study on in-situ petrochemical recycled water-stabilized gravel. The results show that the in-situ granulated recycled aggregate of old concrete slab has good physical and mechanical properties and can be applied to cement stabilized macadam of asphalt pavement. The 7d unconfined compressive strength of recycled cement stabilized macadam can meet the strength requirements of asphalt pavement base and subbase.