A knitting method and an apparatus for a cylindrical biaxial weft-knitted three-dimensional knitted structure. The biaxial three-dimensional knitted structure comprises two weft plain stitch structures (7, 7′), a group of spacer yarns (416), two groups of weft inserting yarns (415, 415′) and a group of warp inserting yarns (43), wherein the two groups of weft inserting yarns are used for selective weft inserting on a needle dial (11) or a needle cylinder (13), the warp inserting yarns are positioned between the two groups of weft inserting yarns, the two weft plain stitch structures are connected with each other by the group of spacer yarns, for jointly clamping the weft inserting yarns and the warp inserting yarns, in order to form a biaxial weft-knitted three-dimensional knitted structure. Such three-dimensional knitted structure improves the mechanical properties of three-dimensional knitted fabrics; by increasing the interval between the needle dial and the needle cylinder, the thickness of the knitted structure is increased, which is suitable for the reinforced structure of high-performance structural and functional composite materials, and expand the field of the use of the knitted structures.