in this paper, we study some properties of analytic extension of a $n$th roots of $m$-hyponormal operator. we show that every analytic extension of a $n$th roots of $m$-hyponormal operator is subscalar of order $2k+2n$. as a consequence, we get that if the spectrum of such operator $t$ has a nonempty interior in $mathbb{c}$, then $t$ has a nontrivial invariant subspace. finally, w...