The disclosure claims a method and a device for transmitting a Position Reference Signal (PRS) subframe. In the disclosure, the network side configures certain channels or signals according to the configuration condition of the PRS, or the network side configures the PRS according to the configuration condition of certain channels or signals; the receiving side correctly identifies the length of Cyclic Prefix (CP) according to the configuration information issued by the network side, so as to correctly measure and accurately receive the channels or signals sent by the network side. The disclosure overcomes the technical problem in the conventional art that the length of CP is ambiguous, so that the signals cannot be measured and accurately received by the receiving side.