Method for large-space three-dimensional entity paying off

The invention discloses a method for large-space three-dimensional entity paying off. The method comprises the first step of establishing a coordinate origin and make a mark well; the second step of performing multi-station derived point conversion on the mark, and obtaining a two-dimensional coordinate system; the third step of adding an elevation value to the two-dimensional coordinate system in combination with a site one-meter line, and forming a three-dimensional coordinate system; the fourth step of establishing a site model; the fifth step of performing fitting on the site model and a three-dimensional design model; the sixth step of finding out a control line for the three-dimensional design model and finding out a three-dimensional coordinate value of a control point of the control line in the three-dimensional coordinate system; and the seventh step of performing site point releasing and paying off according to the three-dimensional coordinate value. The method can completely replace a traditional two-dimensional plane to perform paying off on the spot, the problem that in large spaces and complex spaces, paying off cannot be performed or cannot be performed accurately through a traditional paying off method is solved, working efficiency and the accuracy in the space paying off are improved, and accordingly more accurate bases are provided for later period site construction.