The invention discloses a method and a device for acquiring channel state information and relates to the technical field of communication. By the method and the device, signaling overhead and feedback overhead can be reduced, and the operating complexity of user equipment (UE) is reduced. According to the scheme provided by the embodiment of the invention, any one of at least two cells sends the preset sending time of a reference signal (RS) and a preset frequency point of the RS to the UE; each of at least two cells or a cell combination sends the RS to the UE through different RS resources according to the preset sending time of the RS and the preset frequency point of the RS, and receives a measurement result which is sent by the UE; and the measurement result comprises channel state information (CSI) between any one of at least two cells or the cell combination and the UE. The method and the device provided by the embodiment of the invention are applicable to acquisition of the CSI between a plurality of cells and the UE.