In geometry, the **snub square antiprism** is one of the
Johnson solids (*J*_{85}).
It is one of the elementary Johnson solids that do not arise from "cut and paste" manipulations of the Platonic and Archimedean solids.
The 92 Johnson solids were named and described by Norman Johnson in 1966.

It can be thought of as a square antiprism with a chain of triangles inserted around the middle. A similar effect can be achieved with a triangular antiprism (which is an octahedron), resulting in an icosahedron.