A new forward-secure threshold digital signature scheme which based on multiplicative secret sharing and strong RSA assumption is put forward in this paper. The scheme has the following property: It have the property of forward security, even if more than the threshold numbers of players are compromised, it is not possible to forge the signature which is related to the past. This property is achieved while keeping the public key fixed and updating the secret keys at regular intervals. Assuming that factoring is hard, we proved that this scheme is security in the random oracle model.