Plane transformation technique is an effective algorithm in deinterleaving pulses, the key technique contains two aspects: characteristic curve searching and recognizing.To characteristic curve searching, the traditional way which depends on manpower takes time and energy ,also limits automatic operation; To characteristic curve recognizing, there is only initial description and no executive solution. Considering the weakness above, pulse points’ features are studied, automatic algorithms are designed for selecting characteristic curves, recognizing rules are presented for different types. The searching algorithm, which does not rely on intial pulse’s selection, is applicable to line and curve, the recognizing algorithm is practical and effective, finally, automatic deinterleaving pulses is realized. Simulations testify the efficiency.