In a (

t

n

) threshold signature scheme

any sub set comprising at least t members is capable of signing any message

and incapable otherwise.The focuses of this paper are to propose a ID-based (

t

n

) threshold signature scheme without random oracle based on Paterson’s signature scheme which is also without random oracle

and to analyze the validity and the security of the scheme as well.An important feature of our scheme

in which partial signatures can be expediently generated by participants under the discrete logarithm problem and any pubic verifier can check the validity of partial signatures and threshold signatures

is that any attacker

however

cannot obtain system secret value through the public information or by eavesdropping some partial signatures and threshold signatures

and neither can he forge partial signatures.Given the knowledge of all the participants

’ secret values

a threshold signature cannot be forged.This method is secure in various possible attacks.