The invention discloses a 12-station adjustable fly-cutter head structure for a lathe. The 12-station adjustable fly-cutter head structure comprises a fly-cutter head body, a fly-cutter head cover isconnected to the top of the fly-cutter head body through screws, fixing grooves are formed in the outer side of the fly-cutter head body at equal intervals, and cutter grooves are formed in the positions, located on one sides of the fixing grooves, of the outer side of the fly-cutter head body. The 12-station adjustable fly-cutter head structure is compact in structure, easy and convenient to operate and high in practicability, a tool can be rapidly and accurately adjusted by arranging forward and reverse screws, the tool can extend outwards or be stored inwards in a tool groove, and comparedwith traditional manual beating adjustment, the length error of the tool extending out of or stored in the tool groove is greatly reduced, so that the machining precision of the lathe is greatly improved. Meanwhile, the fly-cutter head made of a 7074 aviation aluminum material is arranged, so that the overall weight of the equipment is reduced, the centrifugal force is reduced, the machining efficiency is improved, the product is more attractive in appearance in the using process, the machining cost is low, and the market requirement is met.