This paper deals with a new receiver scheme that uses the same principle as turbo codes and called, for this reason a turbo equalizer. This receiver associates an equalizer and a soft ouput channel decoder through an iterative process. It is well suited for transmissions over channels having a delay spread of many symbol durations and using M-QAM modulation. In certain cases, the turbo-equalizer can totally overcome the channel frequency selectivity without increasing the level of the noise and thus, this receiver can achieve the same performance as a non selective Gaussian Channel with coding.