The structure of human-machine interface in combine harvester cab was analyzed in terms of ergonomics, then, the priorities of the components were calculated using the modified method of TOPSIS, based on the interview and investigation to 2 designers in the corporation and 45 experienced drivers. The results showed that components used in emergency and frequently are prior to others. Therefore the procedure is more scientific and effective combined with both subjective and objective methods, and the conclusion could be applied to design or evaluate the combine harvester cab. 