A manufacturing method for a bioabsorbable bone screw capable of being developed under X-ray includes the following steps: providing an injection molding machine, a mold, a polylactic acid and a nano-scale ferrous ferric oxide. The mold comprises a bone screw model. The injection molding machine is coupled with the mold. A parent raw material is formed by blending the polylactic acid and the nano-scale ferrous ferric oxide； next, granulating the parent raw material to form a raw material particle； and, supplying the raw material particle into the injection molding machine. The injection molding machine may enable the raw material particle to be heated and pressurized into a predetermined state and supply the raw material particle in the predetermined state to the mold, so the raw material particle in the mold may be formed as the bone screw model according to the shape of the bone screw model. The bioabsorbable bone screw capable of being developed under X-ray comprises a spiral portion and a cap. The spiral portion is of a cylindrical shape. The cap is disposed at one end of the spiral portion and outwardly extended from the spiral portion. The cap and the spiral portion are formed as a whole and are made of polylactic acid and nano-scale ferrous ferric oxide.一種可於x-光下顯影之生物可吸收性骨釘之製作方法，係包含下列步驟：提供一射出成型機、一模具、一聚乳酸及一奈米級四氧化三鐵，該模具具有一骨釘模型，該射出成型機與該模具相連接，混煉該聚乳酸及該奈米級四氧化三鐵，以形成一母原料，接著對該母原料進行造粒，以形成一原料粒，再提供該原料粒至該射出成型機中，該射出成型機將該原料粒加熱加壓至一預定狀態，並提供該預定狀態的該原料粒至該模具中，使該模具中的該原料粒以該骨釘模型形狀形成該骨釘模型。其中該可於x-光下顯影之生物可吸收性骨釘，係包含一螺旋部，以及一帽型。該螺旋部具圓柱狀外型，而該帽型設置於該螺旋部一端，且自該螺旋部向外延伸。該帽型及該螺旋部為一體成型製作，且該帽型及該螺旋部以一聚乳酸及一奈米級四氧化三鐵所製作。
