  We consider the evolution of the vacuum energy in the DGP model according to
the holographic principle under the assumption that the relation linking the IR
and UV cut-offs still holds in this scenario. The model is studied when the IR
cut-off is chosen to be the Hubble scale $H^{-1}$, the particle horizon $R_{\rm
ph}$ and the future event horizon $R_{\rm eh}$, respectively. And the two
branches of the DGP model are also taken into account. Through numerical
analysis, we find that in the cases of $H^{-1}$ in the (+) branch and $R_{\rm
eh}$ in both branches, the vacuum energy can play the role of dark energy.
Moreover, when considering the combination of the vacuum energy and the 5D
gravity effect in both branches, the equation of state of the effective dark
energy may cross -1, which may lead to the Big Rip singularity. Besides, we
constrain the model with the Type Ia supernovae and baryon oscillation data and
find that our model is consistent with current data within $1\sigma$, and that
the observations prefer either a pure holographic dark energy or a pure DGP
model
