  Applying the holographic method, we investigate correlation functions of
boundary and defect conformal field theories. To describe boundary conformal
field theory, we consider an end of the world brane in an asymptotic AdS space
which behaves as a boundary in the dual conformal field theory. In this
holographic setup, we calculate correlation functions involving the reflection
effect at the boundary. We show that, when the end of the world brane has no
degrees of freedom, the holographic calculation reproduces the correlation
functions known in the boundary conformal field theory. When the boundary has
nontrivial boundary entropy, we calculate one- and two-point functions
nontrivially relying on the boundary entropy. We further study correlation
functions of defect conformal field theory after introducing a $p$-brane. We
directly derive a bulk-to-defect two-point function without introducing an
image operator and determine the coefficient of the two-point function exactly
in the holographic setup.
