The invention discloses a construction method of an annular proving road three-dimensional cambered surface using foam light-weight soil. As a casting material, foam light-weight soil is used for casting; in the casting process, a base part and a cambered surface part are constructed in sequence. Particularly, the base part is constructed section by section, each section is 20-40m long, every two sections are in step transition, casting is carried out layer by layer in each section, the casting height at each layer is not greater than 1m; the cambered surface part is divided into multiple areas to be constructed, forming molds are made according to the divided areas before construction, and then the casting is carried out layer by layer. The construction method has the advantages of small post-construction settlement, short construction cycle, low construction cost and the like.