The present invention discloses a method for transmitting information in a closed loop multiple antenna system. The method includes that: a transmission apparatus receives information transmitted from a reception apparatus, wherein the information includes codeword index information; the transmission apparatus selects a corresponding codeword from a double-layer-structure-based codebook according to the codeword index information; the transmission apparatus generates a precoding matrix according to the selected codeword; the transmission apparatus performs precoding for data to be transmitted according to the precoding matrix; the transmission apparatus transmits the precoded data to the reception apparatus. The present invention can enable a formed and used codebook to match channel distribution characteristic of a dual-polarized antenna as much as possible, and minimize performance loss brought by codebook quantization, thereby performance of a precoding system can be effectively improved.