We propose objectively assessing endoscopic sinus surgery (ESS) skills by measuring the force applied to a patient model. We collected data on 16 subjects performing gauze packing task using a precise human nasal model with a six-degree-of-freedom force/torque sensor. Mann-Whitney's U test was used to analyze their performance. Intermediates (ESS: 10-50 cases) used significantly greater force than students or experts (ESS: over 150 cases) at the 5 % level. Maximum force improved only among experts. These results imply that young surgeons pay too little attention to force applied to patients or tissues.