A mobile terminal with a horizontality display function is provided. In the mobile terminal, a body plane is formed at one side of an exterior of a body of the mobile terminal, and an acceleration sensor is installed parallel to the body plane and detects an acceleration corresponding to a physical change with reference to a reference XY horizontal plane. A memory stores preset sensor offset value and sensor sensitivity value of the acceleration sensor, and a controller calculates inclination angles at which the body plane is inclined with respect to the reference XY horizontal plane, using the sensor offset value and the sensor sensitivity value stored in the memory. A horizontality display unit displays as an image a current horizontality detected by the controller on the basis of the calculated inclination angles with respect to the reference XY horizontal plane.