Keloid pathogenesis occurs due to the longer duration of inflammation and the increase in the production of several factors such as TGF-¦Ā1 that causes the increase of fibroblast proliferation and collagen synthesis. The role of B4 Leukotriene (LTB4) in keloid pathogenesis particularly in the inflammation phase and tissue proliferation has not been clearly elucidated. The present study was to analyze the levels of LTB4, TGF-¦Ā1 and collagen in keloid fibroblast and normal skin fibroblast. Fibroblasts were cultured by applying explant method to the keloid and normal skin of the petient with the keloid. The measurement of the levels of LTB4, TGF-¦Ā1 and collagen was conducted by using Elisa method and triplicate was conducted subsequently. Statistic testing was performed through unpaired t test. The experiment was carried out in cell culture laboratory of The Faculty of Medicine Padjajaran University Bandung. The levels of LTB4, TGF-¦Ā1 are higher in keloid fibroblast, despite the fact that it does not show statistically significant difference. The level of collagen 1 is higher than that of collagen 3 in keloid fibroblast. Leukotriene B4 (LTB4) is one of the derivative of arachidonic acid that plays the role as lipid mediumtor of inflammation and fibroblast chemoattractant. The levels of LTB4, TGF-¦Ā1, collagen 1 and collagen 3 increase in keloid fibroblast. Such a result shows the role of LTB4 in the inflammation process that stretches in keloid pathogenesis.