A mobile power adapter having an electric socket for power input, multiple adapter ports for power output, a power supply unit for converting input power supply into desired output power supply for output through the adapter ports, and a monitoring unit for monitoring the temperature inside the mobile power adapter and the operation status of the power supply unit on electric voltage, electric current, power consumption status and total wattage for enabling the monitoring data to be displayed on a display screen on the outside wall of a housing of the mobile power adapter.