In geometry, the **hexagonal prism** is a prism with hexagonal base. This polyhedron has 8 faces, 18 edges, and 12 vertices.

Since it has eight faces, it is an octahedron. However, the term *octahedron* is primarily used to refer to the *regular octahedron*, which has eight triangular faces. Because of the ambiguity of the term *octahedron* and the dissimilarity of the various eight-sided figures, the term is rarely used without clarification.

Before sharpening, many pencils take the shape of a long hexagonal prism.

If faces are all regular, the hexagonal prism is a semiregular polyhedron, more generally, a uniform polyhedron, and the fourth in an infinite set of prisms formed by square sides and two regular polygon caps. It can be seen as a **truncated hexagonal hosohedron**, represented by Schläfli symbol t{2,6}. Alternately it can be seen as the Cartesian product of a regular hexagon and a line segment, and represented by the product {6}×{}. The dual of a hexagonal prism is a hexagonal bipyramid.

The symmetry group of a right hexagonal prism is *D*_{6h} of order 24. The rotation group is *D*_{6} of order 12.

As in most prisms, the volume is found by taking the area of the base, with a side length of
a
, and multiplying it by the height
h
, giving the formula:

V
=
3
3
2
a
2
×
h

The topology of a uniform hexagonal prism can have geometric variations of lower symmetry, including:

It exists as cells of four prismatic uniform convex honeycombs in 3 dimensions:

It also exists as cells of a number of four-dimensional uniform 4-polytopes, including:

This polyhedron can be considered a member of a sequence of uniform patterns with vertex figure (4.6.2p) and Coxeter-Dynkin diagram . For *p* < 6, the members of the sequence are omnitruncated polyhedra (zonohedrons), shown below as spherical tilings. For *p* > 6, they are tilings of the hyperbolic plane, starting with the truncated triheptagonal tiling.