Group authentication method based on threshold secret sharing

The invention discloses a group authentication method based on threshold secret sharing. The group authentication method comprises the following steps of marking n group members as [Ui, i=1,2,...,n]; generating and distributing two secret shares (s1i,s2i) by a secret distributor SD for each group member Ui by means of a (t,n) threshold secret sharing solution; generating and distributing 2*(t-1) secret shares (s1i,s2i) for a group authentication server AS, i=n+1,..., n+t-1; in authentication, if authentication to m users is required, generating two tokens by each authenticated user Ui by means of the secret shares (s1i,s2i) of his own; and performing unified authentication or one-by-one authentication on m users to be authenticated by the group authentication server. The group authentication method can be used for verifying whether all users are legal in one time, and furthermore can quickly and effectively determine all non-group-members on condition that non-group-members exist.