AbstractThe emergence of the artificial intelligence urgently requires novel devices to handle massive data and bionic simulations. As one of new generation memory devices, memristor has great potential in information storage and brain‐like learning due to its merits, such as low energy consumption, high speed and etc. In addition, the randomness for the generation and breakage of the conducting filaments in the memristor can generate the true random numbers and realize the image encryption. In this work, the ITO/Cs2AgBiBr6/Al based devices exhibit prominent resistance variation characteristics and long‐term environmental stability (≥6 months). Additionally, the flexible PET/ITO/Cs2AgBiBr6/Al devices are assembled and measured resistance variation properties, which are adopt to realize the cryptographic processing of image information. The synaptic plasticity of the memristor is also verified, including paired pulse facilitation and spiking timing‐dependent plasticity. Finally, nociceptive responses are also simulated with the memristor via imposing different voltage. Nociceptive characteristics including “threshold,” “relaxation,” and “sensitization” have been successfully determined. The work provides possibility for lead‐free flexible perovskite memristors in information security and biomimicry.