The present invention relates to a CDMA system, which, in part, uses serial and parallel interference cancellation methods to overcome disadvantages of a method of detecting single user, and comprises a feedback loops for providing reproduced signals to respective inputs of detectors, and a means for controlling an operation for the detectors to attribute to interference cancellation process. The detectors to contribute to interference cancellation process can be also selected group by group. It is used to switch off only detectors contributing to interference cancellation process in progress and detectors contributing to previous interference cancellation, providing a adaptive serial and parallel mixed interference cancellation method for increasing performance and capacity of the CDMA system.