let $g={rm sl}_2(p^f)$ be a special linear group and $p$ be a sylow $2$-subgroup of $g$, where $p$ is a prime and $f$ is a positive integer such that $p^f>3$. by $n_g(p)$ we denote the normalizer of $p$ in $g$. in this paper, we show that $n_g(p)$ is nilpotent (or $2$-nilpotent, or supersolvable) if and only if $p^{2f}equiv 1,({rm mod},16)$.