  In the article, we investigate the diquark-diquark-antiquark type fully-heavy
pentaquark states with the spin-parity $J^P={\frac{1}{2}}^-$ via the QCD sum
rules, and obtain the masses $M_{cccc\bar{c}}=7.93\pm 0.15\,\rm{GeV}$ and
$M_{bbbb\bar{b}}=23.91\pm0.15\,\rm{GeV}$. We can search for the fully-heavy
pentaquark states in the $J/\psi \Omega_{ccc}$ and $\Upsilon \Omega_{bbb}$
invariant mass spectrum in the future.
