A micro-head mounted display device that may be detachably affixed to eye-glasses and a method for controlling the same are disclosed. A method for controlling a detachable HMD device, detecting that the HMD device is affixed to eye-glasses, acquiring identification information of the eye-glasses, acquiring a look up table related to the identification information, receiving an input signal generated when the eye-glasses to which the HMD device is affixed are touched, from the sensor unit, acquiring a control input related to the input signal from the look up table, and performing a function corresponding to the control input.