  We introduce entanglement measures to describe entanglement in a
three-particle system and apply it to studying broadcasting of entanglement in
three-particle GHZ state. We show that entanglement of three-qubit GHZ state
can be partially broadcasted with the help of local or non-local copying
processes. It is found that non-local cloning is much more efficient than local
cloning for the broadcasting of entanglement.
