A method for quantum key output is disclosed. The method may be implemented by a first quantum key management device. The method may comprise obtaining a first key acquisition request from a first data device, acquiring a first quantum key from a first quantum key distribution device, according to the obtained first key acquisition request, storing the acquired first quantum key in a same management device address range as a corresponding second quantum key acquired by a second quantum key management device, performing a first consistency verification including determining whether the first quantum key is the same as the second quantum key, and sending the first quantum key to the first data device, if the first quantum key is determined to be the same as the second quantum key.