Embodiments of the present invention relate to an interference cancellation method and system. The interference cancellation system of the present invention includes a centralized cancellation unit and at least two signal processing units, where at least a part of signal processing units in the at least two signal processing units are configured to detect at least a part of user signals in all user signals input into the interference cancellation system and reconstruct the detected user signals; the centralized cancellation unit is configured to perform cancellation on reconstructed signals and the user signals input into the interference cancellation system; and the at least two signal processing units are configured to detect, according to a residual signal after the cancellation, the user signals input into the interference cancellation system and output the detected signals.