The invention discloses a method for code channel detecting that can be used in the code dividing multi address system with the exclusive corresponding relationship between every channel estimating window and every channel code. It includes the following steps: when the receiver receives the signal, the channel estimating and post process would be performed based on the basic midamble code sent from the system to gain channel response of every corresponding basic midamble code; determining signal channel estimating window; determining activated code channel corresponding to signal channel estimating window; taking multi-user detecting by using the activated code channel. The invention could accurately determine signal channel estimating window, exactly orient the channel code, and realizemulti-user detecting.