Embodiments of this disclosure provide a method and apparatus for performing multiuser superposition transmission over repetition-based transmission and a system. In this embodiment, the method includes: an eNB transmits repetition configuration information or repetition configuration information and modulation scheme information of second UE utilizing a repetition-based transmission technique to first UE paired with the second UE for performing MUST transmission, so that the first UE detects data of the second UE and performs interference cancellation according to the repetition configuration information or the repetition configuration information and the modulation scheme information of the second UE, so as to obtain data of the first UE. With the embodiments of this disclosure, unnecessary signaling overhead and repeated detection may be avoided, thereby improving performance and efficiency of MUST transmission.