Let $k$ be a field of characteristic not equal to $2,3$, $J$ the exceptional Jordan algebra over $k$. Then the representation $V=J\otimes k^2$ of $G=GE_6\times GL(2)$ is prehomogeneous. Let $P$ a relative invariant polynomial and $V^{ss}_k=\{x\in V_k | P(x)\not=0\}$. We have determined the arithmetic interpretation of the set $G_k\backslash V^{ss}_k$ of rational orbits and the talk is about this interpretation.