The kapok fibers which are the functional fiber materials having natural hollows are environment friendly materials the demand and interest of which are increasing. The kapok fibers are environment friendly and natural hollow fibers which are 5-8 times lighter than cottons and have excellent performances in thermo keeping property, air permeability, bulkiness and resilience. In this study, the pretreatment according to the dyeing behaviors of kapok fibers were studied. Pretreatment(scouring, bleaching) were a variety of conditions. Scouring and bleaching, images of changed surfaces and cross-sections and dyeing behaviors of the dye-o-meter according to the concentration measured in meters and compared. Although the final exhaustion ratio of the kapok fibers scoured with a high concentration recipe was almost as same as that of the kapok fibers bleached with a high concentration recipe, the initial absorption speed of the kapok fibers scoured with the high concentration recipe was faster than that of the kapok fibers bleached with the high concentration recipe.