The invention provides a mobile network number carrying inquiring method and a mobile network number carrying inquiring device, wherein the mobile network number carrying inquiring method comprises that a first service switching point obtains number information of a called mobile terminal, sends an inquiring request to a fixed-line users data center and inquires the number information of the mobile terminal carried in the inquiring request so that the fixed-line users data center can inquire current contract operator information corresponding to the number information of the mobile terminal in a mobile network number carrying data base, the first service switching point obtains the current contract operator information corresponding to the number information of the mobile terminal which is sent by the fixed-line users data center, and a speech path route from a calling fixed network terminal to the called mobile terminal is connected with a mobile network corresponding to a current contract operator according to the current contract operator information.