An apparatus for managing power of a mobile terminal includes: a first voltage regulating unit that changes the level of power from an external power source to a first level; a second voltage regulating unit that changes the level of power from the first voltage regulating unit or the external power source to a second level; and a switching unit that switches an output of the external power source or the first voltage regulating unit to the second voltage regulating unit. The coverage of an output voltage of the mobile terminal can be extended and the cost of the power management apparatus can be reduced.