A multi-user code division multiple access communication method, and corresponding transmitter and receiver include: the transmitter determines a complex-valued spreading sequence to be used by the transmitter, herein each element of the complex-valued spreading sequence is a complex number and values of real and imaginary parts of all elements in the complex-valued spreading sequence are from an M-element set of real numbers, and M is an integer larger than or equal to 2; the transmitter performs spreading processing on data symbols to be sent by using the complex-valued spreading sequence to generate a spread symbol sequence; and sends the spread symbol sequence. The receiver receives signals transmitted by multiple transmitters, and performs reception detection by using an interference cancellation signal detector, herein the complex-valued spreading sequences used by the multiple transmitters are used during detection.