We classify the five-dimensional $C^\infty$ Anosov flows which have $C^\infty$-Anosov splitting and preserve a smooth pseudo-Riemannian metric. Up to a special time change and finite covers, such a flow is $C^\infty$ flow equivalent either to the suspension of a symplectic hyperbolic automorphism of $\mathbb{T}^{4}$, or to the geodesic flow on a three-dimensional hyperbolic manifold.
AMS 2000 Mathematics subject classification: Primary 34Cxx; 34Dxx; 37-XX