  Let $\mathcal{H}^{(r)}_n$ be the set of all connected $r$-graphs with given
size $n$. In this paper, we investigate the effect on the spectral radius of
$r$-uniform hypergraphs by grafting or contracting an edge and then give the
ordering of the $r$-graphs with small spectral radius over
$\mathcal{H}^{(r)}_n$, when $n\geq 20$.
