A electronic pet contains a diving device which includes a sealed main body with at least one flexible portion disposed on at least one part of the main body wherein the sealed main body is sealed from water external to the sealed main body by the at least one flexible portion together with the main body, and an actuator, directly connected to the flexible portion through a transmission shaft, wherein the actuator is adapted for controlling the air density of the diving device by pulling or pushing the flexible portion inwards or outwards through the transmission shaft respectively. The electronic pet also includes a driving device, a sensing device used to sense light, sound and contact/non-contact stimulations from an external environment, a signal transceiver device used to transceive signals to and from devices other than the electronic pet, and a processor.