Let X be a Stein manifold of dimension $$n\ge 2$$ satisfying the volume density property with respect to an exact holomorphic volume form. For example, X could be $$\mathbb {C}^n$$ , any connected linear algebraic group that is not reductive, the Koras–Russell cubic, or a product $$Y\times \mathbb {C}$$ , where Y is any Stein manifold with the volume density property. We prove that chaotic automorphisms are generic among volume-preserving holomorphic automorphisms of X. In particular, X has a chaotic holomorphic automorphism. A proof for $$X=\mathbb {C}^n$$ may be found in work of Fornaess and Sibony. We follow their approach closely. Peters, Vivas, and Wold showed that a generic volume-preserving automorphism of $$\mathbb {C}^n$$ , $$n\ge 2$$ , has a hyperbolic fixed point whose stable manifold is dense in $$\mathbb {C}^n$$ . This property can be interpreted as a kind of chaos. We generalise their theorem to a Stein manifold as above.