The objective of this study was to observe the effect of dietary calcium(Ca) level on colonic mucosal levels of cell proliferation, 1, 2-diacylglycerol(DAG), TXB2, PGE2 and phospholipid fatty acid composition which have been known as biomarkers for colon cancer. One hundred male Sprague Dawley rats, at 7 weeks of age, were divided into two fat type groups. Each group of which was further divided into two Ca level groups. Each rt was intramuscularly injected with 1, 2,-dimenthylhydrazine(DMH) for 6 weeks (total dose of 180mg/kg body weight) and simultaneously fed one of four experimental diets containing 15% dietary fat(corn oil or perilla oil )and 0.3% or 1.0% Ca by weight for 20 weeks. Compared to corn oil, perilla oil significantly reduced cell proliferation by decreasing labeling index, proliferating zone, crypt length in colonic mucosa and colonic mucosa and colonic mucosal levels of DAG, TXB2 . PGE2 and phospolipid (PL) arachidonic acid distribution. The effect of Ca on biomarketrs was different depending on the type of dietary fat comsumed . Ca effect of Ca on biomarkers was different depending on the type of dietary fat comsumed. Ca effect was not significantly shown in the PO group, but it was significant in the CO group in which high Ca(1.0%) decreased the levels of levels of PL-C20 : 4(%), DAG and PGE2 . However , high Ca supplementation had shown only the trends of improving cell proliferation. Overall , high dietary Ca significantly reduced cell proliferation by inhibiting the synthesis of eicosanoid and DAG with reduced distribution of PL-C20 : 4 , which may have resulted in lower activation of PKC through reduced signal transduction. Since a high level of dietary Ca was more effective in reducing the risk factor against colon cancer in corn oil fed rats, it could be suggested that a higher amount of dietary Ca be consumed , especially when more vegetable oil rich in linoleic acid is included in the diet.