Research conclusions ： ( 1 ) The result of the tests shows that types and dose of additive are determined through compaction test，unconfined compression test and engineering characteristics ； grain composition，strength and stability of old road mixture are compared with cement - stabilized recycled mixture. And optimum water content on 5% cement - stabilized sandy soil mixture was respectively 12. 1 % which shows that intensity and stability of cement - stabilized recycled mixture is better， and can meet the requirement on pavement base. (2) Engineering evaluation projects is established in detail. It mainly includes present situation， structural bearing capacity and the performance of old mixture，etc. (3) Through engineering practice， it points out the method of equipment matching on cold in - place recycling units and adding method of cement and water, and integrative operation method of milling - planing and compacting in cold in - place recycling technology is proposed. (4) Detection results of cold - recycled base show that various indexes of base can meet pavement operating requirements, and regeneration effect is good, which is provided for references to the design and construction of similar cold regenerative base.