  We are aiming to study the $J/\psi \to p\bar{p}\eta'$ decay in an isobar
model and the effective Lagrangian approach. After a careful exploration of the
contributions of the $S_{11}(1535)$, $P_{11}(1710)$, $P_{13}(1900)$,
$S_{11}(2090)$ and $P_{11}(2100)$ resonances, we conclude that either a
subthreshold resonance or a broad $P$-wave state in the near threshold range
seems to be indispensable to describe present data of the $\pi N \to \eta'N$.
Furthermore, at least one broad resonance above $\eta'N$ threshold is
preferred. With this detailed analysis, we could give the invariant mass
spectrum and Dalitz plot of the $J/\psi \to p\bar{p}\eta'$ decay for the
purpose of assisting the future detailed partial wave analysis. It is found
that the $J/\psi \to p\bar{p}\eta'$ data are useful for disentangling the above
or below threshold resonant contribution, though it still further needs the
differential cross section data of $\pi N \to \eta'N$ to realize some of the
resonant and the non-resonant contribution. Our results are enlightening for
the $\eta'N$ production mechanism and the properties of the nucleon resonances
with the mass around 2.0~GeV.
