In order to avoid the flaw of the secret shadow distribution method in the existing secret sharing schemes, a secret shadow distribution method is proposed with the ID-based public key technology integrated, which uses the participant's private key as his master shadow. Firstly, security analyses are made on Zheng's signcryption scheme, which shows his scheme does not offer forward secrecy. Then, an improvement is made on Zheng's signcryption scheme and a new scheme is proposed. Based on the proposed signcryption scheme and the ID-based public key cryptosystem, a new threshold multi-secret sharing scheme is proposed. The problem of the secret shadow distribution is well resolved, and no information exchange is needed between the secret dealer and each participant in advance. The secret shadow distribution can be processed during the secret distribution. At the same time, the proposed scheme offers forward secrecy. That is to say, even if the private key of the secret dealer is exposed, the security of the shared secrets will not be threatened. Therefore, the proposed ID-based secret sharing scheme is more secure and effective than others, and it can be more applicable.