A visualization apparatus includes a memory unit and a computing unit. The memory unit stores a circulation model in which a vascular network, of an organ, having a diameter equal to or smaller than a predetermined value is defined on a two-dimensional plane, and a simulation result of a blood flow in the vascular network of the circulation model. The computing unit transforms the circulation model into a three-dimensional structure including the vascular network located on a cylindrical surface of a cylinder, and displays the simulation result on the three-dimensional structure.