The invention discloses a network expansion method and device. The method comprises the steps of in a pre-stored first correspondence relationship between a first user perception rate threshold and a first network expansion index threshold, obtaining a second correspondence relationship of a region to be evaluated between a second user perception rate threshold and a second network expansion index threshold; determining a current user perception rate and a current network expansion index of the region to be evaluated; comparing the current user perception rate and the current network expansion index with the second user perception rate threshold and the second network expansion index threshold in the second correspondence relationship; and carrying out carrier frequency expansion for cell to be expanded when the obtained comparison result conforms to a cell expansion condition. The invention is used for solving the problem that generally, an LTE network mode is based on the standard mainly from corresponding threshold requirements given by the LTE network load and network planning and design requirements and the limitation is high.