  The spectrum of the $k$-power hypergraph of a graph $G$ is called the
$k$-ordered spectrum of $G$.If graphs $G_1$ and $G_2$ have same $k$-ordered
spectrum for all positive integer $k\geq2$, $G_1$ and $G_2$ are said to be
high-ordered cospectral. If all graphs who are high-ordered cospectral with the
graph $G$ are isomorphic to $G$, we say that $G$ is determined by the
high-ordered spectrum.In this paper, we use the high-ordered spectrum of graphs
to study graph isomorphism and show that all Smith's graphs are determined by
the high-ordered spectrum.And we give infinitely many pairs of trees with same
spectrum but different high-ordered spectrum by high-ordered cospectral
invariants of trees,it means that we can determine that these cospectral trees
are not isomorphism by the high-ordered spectrum.
