We propose a joint channel and data estimation scheme which does not require the training data in multicarrier direct-sequence multiple access (MC-DS/CDMA) systems. In order to eliminate the multiple access interference (MAI), the minimum output energy (MOE) filter is first used on each subcarrier because it can be implemented without the knowledge of the channel coefficients. Then, the channel coefficients of the subcarriers are estimated using the MOE filter output signals, and they are used to combine the MOE filter output signals to maximize the output signal-to-interference plus noise ratio (SINR). Simulation results show that the proposed scheme is much superior to the previous schemes especially in the near-far environment.