In order to improve the efficiency of deterministic key distribution, a quantum key distribution scheme based on GHZ states entanglement swapping was proposed. By sharing a pair of GHZ states between communicators, Bob can deduce deterministic key from classic information which was sent by Alice who took entanglement and measurement operation. Compared with other scheme based on GHZ entanglement state, two GHZ states produced by Bob in the proposed scheme and particles are distributed not by Alice, but Bob. Security analysis results show that any eavesdropper can be found in time. The proposed scheme has high distribution efficiency in that all the GHZ states can be used to transmit information except those chosen for checking eavesdroppers, it can reach the distribution efficiency at 60% and simple to operation.