Methods for multi-user detection in a CDMA-based channel for use in a base station receiver are provided. Signals, each including a CDMA code, are received. Correlation operations are performed on CDMA codes of received signals respectively to obtain corresponding first correlation values. CDMA codes are divided into first and second code groups according to a threshold and corresponding first correlation values. An interference cancellation procedure is performed on received signals to remove signals corresponding to first code group therefrom and to obtain a removed signal. Correlation operations are performed on CDMA codes of removed signal to obtain corresponding second correlation values. Each first correlation value is subtracted from a corresponding second correlation value and compared with a threshold to generate a comparison result. Whether CDMA codes within first code group are correct are determined according to comparison results, wherein the threshold is dynamically adjusted according to comparison results.