Conventional phase-shifting interferometry-based (PSI-based) cryptosystem needs at least two-step phase-shifting.In this work,we propose a phase-shifting-free interferometric cryptosystem,which needs only one interferogram recording.Since the phase-shifting step is not required in the proposed cryptosystem,not only the low encryption speed which is a bottleneck problem of the conventional PSI-based one is solved,but also the setup of the cryptosystem is simplified.A series of simulation experimental results demonstrate the validity and robustness of the proposed cryptosystem.