  The fairness of a secure multi-party quantum key agreement (MQKA) protocol
requires that all involved parties are entirely peer entities and can equally
influence the outcome of the protocol to establish a shared key wherein no one
can decide the shared key alone. However, it is found that parts of the
existing MQKA protocols are sensitive to collusion attacks, i.e., some of the
dishonest participants can collaborate to predetermine the final key without
being detected. In this paper, a multi-party QKA protocol resisting collusion
attacks is proposed. Different from previous QKA protocol resisting $N-1$
coconspirators or resisting $1$ coconspirators, we investigate the general
circle-type MQKA protocol which can be secure against $t$ dishonest
participants' cooperation. Here, $t < N$. We hope the results of the presented
paper will be helpful for further research on fair MQKA protocols.
