Eaves in Korean traditional architecture plays the functional and symbolic roles in creating the appearance of building. Therefore, the length and angle of the eaves vary depending on the scales, characters and structures of building and it is considered that several factors may have influence on deciding the value of eaves. This study classifies the whole factors related to eaves angle, eaves height and eaves protrusion through general review of eaves, examines their correlations and characteristics and compares and analyzes them by the character of building. Eaves angle is the by-product by eaves protrusion and is resulted from the relationship between eaves height and eaves protrusion. Also this study found that the eaves height and eaves protrusion may be different by characters and styles of buildings and they may be assumed by two methods including estimation model (Y=0.4039x+797.77) and statistical value showing intensive distribution.