Number changing notification method and system

The invention relates to a number changing notification method and system. The method comprises: the signaling monitoring platform of a core network, when monitoring a voice call signaling, generating a signaling file of a user dialing recording; the signaling monitoring platform transmitting the singling file to a number changing service platform; the number changing service platform parsing the signaling file, and obtaining caller information, called party information and original called party information; and the number changing service platform, according to the called party information and the original called party information, querying whether a called user already customizes a number changing notification service, if so, obtaining the short message notification content arranged by the called user, generating a number changing notification short message, and then issuing the short message to a caller number through a short message gateway. By using the method and system provided by the invention, a caller user can obtain a notification short message of a new number when dialing the original number of a caller user so that communication exchange between the caller user and the called user is facilitated, at the same time, the trouble of notifying friends of number change one by one is saved, and the problem of affected communication exchange of a user due to notification incompleteness is avoided.