In mathematics, Seifert-Weber space is a closed hyperbolic 3-manifold. It is also known as Seifert-Weber dodecahedral space and hyperbolic dodecahedral space. It is one of the first discovered examples of closed hyperbolic 3-manifolds.

To construct it, notice that each face of a dodecahedron has an opposite face. We will glue each face to its opposite in a manner to get a closed 3-manifold. These faces do not line up, so to glue a pair of faces, rotate clockwise to line up the faces and then add an additional fifth of a complete clockwise rotation.