As an important part of quantum signature, quantum multi-party signature solves the practical signing problem of requiring multiple signers or multiple verifiers. However, most of the existing multi-party signature protocols focus on the situation of multiple signers. Meanwhile the arbitrator is usually introduced to ensure their security. In this paper, we propose a new quantum multi-party signature protocol without arbitrator where multiple signers and multiple verifiers simultaneously appear in it. During the protocol, the strongly nonlocal orthogonal product (SNOP) states are applied to generate the signed messages. According to our analysis, it can be seen that this protocol is resistant to denial and forgery attacks, even if some of the participants collude. We hope the ideas and methods may make positive effects to the further research of quantum signature.