  We investigate the approximate quantum state sharing protocol based on random
unitary channels, which is secure against any exterior or interior attackers in
principle. Although the protocol leaks small information for a security
parameter $\epsilon$, the scheme still preserves its information-theoretic
secrecy, and reduces some pre-shared classical secret keys for a private
quantum channel between a sender and two receivers. The approximate private
quantum channels constructed via random unitary channels play a crucial role in
the proposed quantum state sharing protocol.
