The utility model provides a slip casting union coupling head structure is at least including cover hunch, spray of molten steel pipe, inflation sealing rod, stand pipe, gate valve, steel pipe and screw thread, the cover encircles to set up to manage at the spray of molten steel manages and the stand pipe with the peripheral and fixed spray of molten steel of stand pipe, spray of molten steel pipe set up inflation sealing rod upper end and with inflation sealing rod zonulae occludens, the stand pipe sets up at inflation sealing rod lower extreme, the setting of inflation sealing rod is between spray of molten steel pipe and stand pipe, the steel pipe symmetry sets up at spray of molten steel pipe and stand pipe left side intermediate position to install the gate valve on the steel pipe, the screw thread sets up at the steel pipe left end and closely rabbets at the steel pipe left end, this slip casting union coupling head structure mechanism is scientific, cheap, simple to operate, relies on the inflation stagnant water of sealing rod self, needn't slot to drill on the structure surface and carry out the leaking stoppage, can directly utilize preparation slip casting directly to pour into the chemical grout leak protection into, effectively reduces the time limit for a project, reduces expenses, and the practicality is strong, is fit for using widely.