Objective: To study the absorption and transportation characteristic of xanthotoxol (1), xanthotoxin (2), imperatorin (3), isoimperatorin (4), cnidilin (5), and isopimpinellin (6), which were classified as the linear type furocoumarins, in a model of Caco-2 cell monolayers in human intestinal epithelium. Methods: Caco-2 (the human colon adenocarcinoma cell lines) cell monolayer was used as an intestinal epithelial cell model. The permeability of the six coumarins from apical side (AP side) to basolateral side (BL side) or from BL side to AP side was evaluated. The concentration of the six coumarins was measured by HPLC coupled with UV detector. Transportation parameters and permeability coefficients (Papp) were then calculated, and P app values were compared with the reported values for model compounds, Propranolol and Atenolol. Based on the absorption and transportation characteristic of coumarins 1-6, and psoralen (7), bergaptol (8), bergaptol-O-β-D-glucopyranoside (9), bergapten (10), nodakenin (11), nodakenetin (12), decuroside V (13), umbelliferone (14), osthole (15), angelol-A (16), and angelol-B (17) in a model of Caco-2 cell monolayer, the relationship of absorption and transportation with diversed chemical structures and lipophilicity was reviewed. Results: In the Caco-2 cell monolayer model, the Papp magnitudes of the linear furocoumarins 1-6 were 10-5 cm/s in the bi-directional transport, which was identical with Propranolol. And the permeability of Caco-2 cell monolayer is mainly via passive absorption. Conclusion: The above-mentioned linear furocoumarins 1-6 are well-absorbed compounds. The results show that a significant Sigmoid dependence of permeability on 1g Papp AP→BL and 1g D at pH 7.35 of all 1-17 furocoumarins can be absorbed across intestinal epithelial cells by passive diffusion mechanism.