OBJECTIVE: To evaluate and quantify the medial longitudinal arch of foot using a 3-D foot scanner and 3-D arch measurement program. METHOD: 997 subjects (363 men and 634 women) were selected. The foot length, width, girth and medial longitudinal arch parameters were measured with a 3-D foot scanner (Nexcan(r), K&I, Korea), analysis software (EnFOOT(R), K&I, Korea) and 3-D measurement program of the medial longitudinal arch. RESULTS: The mean arch lengths were 100.3 mm for men, 90.4 mm for women. The mean arch height and arch volume in both genders were 14.7 mm, 12.1 mm and 10.3 cm3, 6.0 cm3, respectively. We compared the arch parameters of both genders by univariate analysis of variance and in most cases the parameters of men were larger than those of women. Moderate positive relationships were found between foot length and arch width of talonavicular joint in cases of men, foot length and length from heel point to distal arch point in both genders (Pearson correlation coefficient > 0.3, p<0.01). CONCLUSION: We evaluated the medial longitudinal arch of Korean feet three dimensionally. These data sould be a useful reference for making shoes, insoles, and orthoses.