A portable electronic includes a main body defining a plurality of mounting holes at corners; a plurality of mounting modules; a plurality of resilient members compressed and mounted in mounting holes of the main body by the corresponding mounting modules; and a control module. The control module includes a MCU; an acceleration transducer connected to the MCU to sample a real-time acceleration value, and a memory connected to the MCU to store a critical acceleration value. The control module controls the mounting modules to release the compressed resilient members so as to eject out the resilient members from the main body, when the real-time acceleration value is larger than the critical acceleration value.