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• Emerging g-DLP technique and shape memory polymers were employed to the dual information encryption. • Reconfigurable geometry and tunable optics provide the encryption and decryption behaviors under the stimulations of temperature and humidity. • The dual information encryption system is erasable, repeatable, and programmable. • The encrypted information system can be stored or decrypted permanently through the different post-processing methods. Dual information encryption such as geometry and transparency switching is highly desirable for preventing the leakage of confidential information and constructing a secure environment which has wide range of applications in privacy protection, anti-counterfeiting, and information security. However, it is still a challenge to develop a novel encrypted strategy and smart material to achieve credible protective capacity for stored information by a facile and programmed manner. Herein, integrating with arbitrary grayscale stereolithography, the hydrophilic ultraviolet (UV) curable shape memory polymers (HU-SMPs) with superior mechanical properties (the tensile strength of 29.39 MPa, elongation of 46.32 %, and the toughness of 1021.98 kJ.m−3) were prepared, which can be used for multifunctional information encryption. During the encrypted process, the HU-SMPs with the performances of high deformable and excellent shape memory behaviors can provide the preprogrammed morphological information and inevitable encryption, while the humidity-responsive of HU-SMPs capable of generating revisable transparency switching that can be encoded as the secondary information encryption. In this way, the dual encrypted information in the HU-SMPs is readable only after sequential shape recovery and fast hydration under heat-stimuli and humidity-stimuli. In addition, with the aid of digitally grayscale drawing, the secondary encrypted information is cyclically displayed and erasable due to the reversible hydration and dehydration process of HU-SMPs. Finally, the encrypted information is also can be permanently storage or decryption by the versatile post-processing methods of UV irradiation after and before decryption, respectively. In short, the design of HU-SMPs that compatible with grayscale digital light process (g-DLP)-based 3D printing, will motivates the future development of smart materials and provides a new insight into the information encrypt fields. [ABSTRACT FROM AUTHOR]