In this paper, a binary joint transform correlator subtracting a power spectrum baesd on a phase shift technique (DBJTC) is presented. A special half wave plate is fabricated. The zero order spectra (i.e., the autocorrelation power spectra) are removed form the joint transform power spectrum using the phase shift technique, so that higher diffraction output and more limited size and relative position of the images in the input plan are obtained. Simulation and optical experimental results show that DBJTC has the advantages of higher efficiency, and better peak-to-sibelabe and signal-to-noise ratios compared with the classical JTC and binarized JTC.