With proxy multisignature, many original signers can delegate their signing power to a proxy signer in such a way that the proxy signer can sign any message on behalf of them. In blind signature, the signer cannot make a linkage between the blind signature and the identity of the requester. Therefore, they are easily applied in electronic commerce. Based on Schnorr signature scheme, a new proxy blind multisignature scheme was proposed. One proxy signer can generate a proxy blind multisignature on behalf of many original signers. This scheme satisfies the security properties of both the blind signature scheme and the proxy multisignature scheme. It has advantages such as low computation load, high efficiency and security, and that the length of signature does not increase when the new original signers join in.