In this paper, we put forward a weak blind quantum signature scheme based on quantum entanglement swapping of Bell states. Different from the existing quantum signature schemes, our scheme can offer two-step verification security services to ensure the validity of the verification. In order to guarantee the unconditional security of the scheme, the quantum key distribution protocol and one-time pad encryption algorithm are employed in our scheme. Besides, the entanglement swapping of Bell states mechanism enhances the security of verification criteria. The proposed scheme has the properties of nonforgeability, nonrepudiation, lindness,and traceability. In this paper, we put forward a weak blind quantum signature scheme based on quantum entanglement swapping of Bell states. Different from the existing quantum signature schemes, our scheme can offer two-step verification security services to ensure the validity of the verification. In order to guarantee the unconditional security of the scheme, the quantum key distribution protocol and one-time pad encryption algorithm are employed in our scheme. Besides, the entanglement swapping of Bell states mechanism enhances the security of verification criteria. The proposed scheme has the properties of nonforgeability, nonrepudiation, lindness, and traceability.