Abstract: A new proxy blind multi-signature scheme based on the intractability of the elliptic curve discrete logarithm problem is proposed.Some methods of attack to the discrete logarithm problem are discussed.The scheme can avoid the cheating from the signers efficiently.The signatory can validate the last signature to discover fake signature,at the same time all members can deal with the emergency according to the error message in time,it also can validate the validity of signatory's public key avoid the cheating by inner users.The scheme takes full advantage of elliptic curve cryptosystem, such as shorter private key,higher signature efficiency and reduces the cost of communication,so it is security and practical.