The invention discloses a
user group information synchronization method,
system and
server, wherein the method comprises the following steps that: a
client and the
server mutually exchange
syncml protocol synchronization capability, and the
syncml protocol synchronization capability at least comprises marks showing whether text / x-group capability is realized or not; and when both the
client and the
server have the text / x-group capability, the server and the
client are interacted so that the
user group information is provided for the client in the synchronization data. During the
address book data synchronization carried out at the user and the network side, the communication information of each contact person can be synchronized, in addition, the group information of each contact person can also be synchronized at the same time, great convenience is brought for the use of
address book information by users, the users can easily lead the group information into a new mobile terminal in one aspect, and all information of the contact person can be completely stored during the contact person information downloading or
backup in the other aspect.