The invention discloses a conical piece reciprocating fluctuation and extrusion forming design method. The conical piece reciprocating fluctuation and extrusion forming design method comprises the following steps: (1) design a process scheme of the composite speed of an extruding upper mold and the composite speed of an extruding lower mold, performing reciprocating pressure application and formation on blanks by the extruding upper mold and the extruding lower mold according to the set speed, and promoting the blanks to generate plastic deformation to achieve the designed shape of the conicalpiece; (2) obtaining the equal effect variable of all the deformation units with the cross section as same as that of the conical piece, and calculating the whole deformation uniformity of the section along with time; (3) optimizing parameters such as fluctuation amplitude and frequency of the composite speed of the extruding upper mold and the composite speed of the extruding lower mold by taking minimal deformation uniformity and forming force as a target; and (4) performing process certification according to the optimal process scheme of the composite speed of the extruding upper mold andthe composite speed of the extruding lower mold to obtain the conical piece with relatively uniform deformation. By the conical piece reciprocating fluctuation and extrusion forming design method, thedeformation uniformity of the conical piece can be improved effectively; meanwhile, the maximal equivalent strain is reduced and the deformation capability of the conical piece is improved.