In geometry, the decagonal prism is the eighth in the infinite set of prisms, formed by ten square side faces and two regular decagon caps. With twelve faces, it is one of many nonregular dodecahedra. The decagonal prism has 12 faces, 30 edges, and 20 vertices. If faces are all regular, it is a semiregular or prismatic uniform polyhedron.
The decagonal prism exists as cells in two four-dimensional uniform 4-polytopes: