The present invention relates to a data input apparatus and a method thereof. The data input apparatus can input data independently or sequentially via a first input or a second input for selecting one of the indication positions or a pair of indication positions of an input unit provided with a plurality of front and back indication positions based on a reference line passing through a reference point, which is a reference position for a base within a finger movement range. When a finger is placed on the input unit, the indication positions of the input unit are easily recognized as front and back corresponding input selection positions based on the reference line or the center of the input unit. Therefore, a user can easily and rapidly input data upon inputting data using the input unit.