Many properties of frequency-hopped spread-spectrum multiple access (FH/SSMA), such as, robustness against frequency selective fading and jamming make it a preferred multiple access communication scheme. But cochannel interference (CCI) can seriously harm the system’s performance. On the basis of the analysis of the CCI pattern of frequency hopped multiple access signal, a new multiuser detection algorithm for canceling the CCI in frequency hopped multiple access systems is proposed. In the proposed scheme, the CCI is canceled by first detecting the frequency hopping slot, and then classifying and regenerating the candidates of the interference pattern from the time-frequency matrix. Both the theoretical analysis and computer simulation results show that compared to the conventional detector and Mabuchi’s detector, this new multiuser detector has lower complexity, better convergence stability, and is suitable for both additive white Gaussian noise (AWGN) channels and Rayleigh fading channels. Many properties of frequency-hopped spread-spectrum multiple access (FH / SSMA), such as, robustness against frequency selective fading and jamming make it a preferred multiple access communication scheme. But cochannel interference (CCI) can seriously harm the system’s performance. On the basis of the analysis of the CCI pattern of frequency hopped multiple access signal, a new multiuser detection algorithm for canceling the CCI in frequency hopped multiple access systems is proposed. In the proposed scheme, the CCI is canceled by first detecting the frequency hopping slot , and then classifying and regenerating the candidates of the interference pattern from the time-frequency matrix. Both the theoretical analysis and computer simulation results show that compared to the conventional detector and Mabuchi’s detector, this new multiuser detector has lower complexity, better convergence stability, and is suitable for both additive white Gaussian noise (AWGN) channels and Rayleigh fading ch annels.