  We study, in the framework of the entanglement harvesting protocol, the
entanglement harvesting of both a pair of inertial and uniformly accelerated
detectors locally interacting with vacuum massless scalar fields subjected to a
perfectly reflecting plane boundary. We find that the presence of the boundary
generally degrades the harvested entanglement when two detectors are very close
to the boundary. However, when the distance between detectors and the boundary
becomes comparable to the interaction duration parameter, the amount of the
harvested entanglement approaches a peak, which even goes beyond that without a
boundary. Remarkably, the parameter space of the detectors' separation and the
magnitude of acceleration that allows
  entanglement harvesting to occur is enlarged due to the presence of the
boundary. In this sense, the boundary plays a double-edged role on entanglement
harvesting,
  degrading in general the harvested entanglement while enlarging the
entanglement harvesting-achievable parameter space.
  A comparison of three different acceleration scenarios of the detectors with
respect to the boundary, i.e., parallel, anti-parallel and mutually
perpendicular acceleration, shows that the phenomenon of entanglement
harvesting crucially depends on the acceleration, the separation between two
detectors and the detectors' distance from the boundary.
