An embodiment of the present application relates to the technical field of wireless communications, in particular to a method, system and device for transmitting pre-coded indication information and determining a pre-coding matrix. In the prior art, the existing codebook is designed for horizontal beamforming/pre-coding, and will reduce the performance thereof if directly applied in three-dimensional beamforming/pre-coding technique. The present application solves the problem. The method in the embodiment of the present application comprises: a user equipment (UE) determines and transmits first pre-coded indication information and second pre-coding indication information, the pre-coding matrix being equal to the function matrix of a first component pre-coding matrix and a second component pre-coding matrix, a sub-matrix on the diagonal of the first component pre-coding matrix being the Kronecker product of two diagonal matrixes, the second component pre-coding matrix being formed by a beam rotation vector equaling to the Kronecker product of two vectors. The embodiment of the present application improves the performance of the three-dimensional beamforming/pre-coding technique.