The invention discloses a three-dimensional modeling method of a complicated block body. The complicated block body is a non-lug body comprising a concave combination air face, the basic idea of the three-dimensional modeling method is that the non-lug body is taken as a combination of a series of lug bodies, and the air face is used for dividing space; sub lug bodies in each sub-region are extracted, and finally a series of sub-lug bodies are combined in a final complicated block body; the three-dimensional modeling method comprises the following main steps of: selecting the air face to divide the block body into two parts on the air face of the non-bug combination, and splitting the parts, wherein if the parts contain no air faces of a concave combination, the parts are lug bodies which can be directed extracted, and if the parts contain the air faces of a concave combination, one air face is selected to repeat the above steps until the residual part does not comprise the air face of the concave combination. The method can finish the modeling of the complicated block body with not revising the classical block body theoretical hypothesis, has a vigorous supplement on the classical block body theory, and has important application value in engineering practice.