  The relation between Loop Quantum Gravity (LQG) and tensor network is
explored from the perspectives of bulk-boundary duality and holographic
entanglement entropy. We find that the LQG spin-network states in a space
$\Sigma$ with boundary $\partial\Sigma$ is an exact holographic mapping similar
to the proposal in arXiv:1309.6282. The tensor network, understood as the
boundary quantum state, is the output of the exact holographic mapping emerging
from a coarse graining procedure of spin-networks. Furthermore, when a region
$A$ and its complement $\bar{A}$ are specified on the boundary
$\partial\Sigma$, we show that the boundary entanglement entropy $S(A)$ of the
emergent tensor network satisfies the Ryu-Takayanagi formula in the
semiclassical regime, i.e. $S(A)$ is proportional to the minimal area of the
bulk surface attached to the boundary of $A$ in $\partial\Sigma$.
