We present an optical encryption method of multiple three-dimensional objects based on multiple interferences and single-pixel digital holography.By modifying the Mach-Zehnder interferometer,the interference of the multiple objects beams and the one reference beam is used to simultaneously encrypt multiple objects into a ciphertext.During decryption,each three-dimensional object can be decrypted independently without having to decrypt other objects.Since the singlepixel digital holography based on compressive sensing theory is introduced,the encrypted data of this method is effectively reduced.In addition,recording fewer encrypted data can greatly reduce the bandwidth of network transmission.Moreover,the compressive sensing essentially serves as a secret key that makes an intruder attack invalid,which means that the system is more secure than the conventional encryption method.Simulation results demonstrate the feasibility of the proposed method and show that the system has good security performance.