Comfortable man-machine interfaces are required for current advanced vehicle systems. This paper aims at investigating the relation between reaction force of switches and human switch operation feeling. We investigate how each reaction force of switches effects the touch feeling of switches via sensory test. The results of factor analysis for the questionnaire data obtained in the sensory test show that the most substantial factor is the feeling expressed by the words “Clear”, “Smooth”, “Stiff”, and “Clicking”. Finally, each feeling described by each word is directly evaluated by reaction force or vice versa on dual scales. The dual scale for reaction forces and degree of feeling can be directly used for designing comfortable switch.