The invention provides a multi-mode terminal, and a CSFB voice business realization method; the multi-mode terminal reads
system messages of a plurality of
GSM adjacent regions under a LTE idle state, and obtains
signal intensity satisfying
residence conditions and each
community location area ID according to the
system messages, thus building a
GSM adjacent region information sheet; the multi-mode terminal switches to the
GSM network and carries a GSM frequency point
list, carries out frequency sweeping, and preferably selects a GSM
community as the candidate
community according to the
signal intensity obtained by frequency sweeping and the GSM adjacent region information sheet, wherein the selected community satisfies
residence conditions, the
system message of the selected community is read, and the selected community has the same ID with a
residence LTE community
location area ID; the multi-mode terminal returns to the selected community from the LTE mode to reside, and starts a calling process. The multimode terminal and the method can omit a residence GSM
community system message reading process and a
location area updating process, thus reducing calling
delay. The invention also provides the GSM adjacent region information sheet maintenance method so as to timely update the information in the information sheet.