Abstract: Objective:To explore the effects of phytosterol ester(PSE) on short chain fatty acids in colon contents of rats fed a high fat diet.Methods:Thirty six-week old SD rats were randomized into four groups.Normal control group was fed a normal chow diet, while other three groups were fed a high fat diet and the two PSE intervention groups were given low(0.05 g/100 g BW·d) and high(0.10 g/100 g BW·d) doses of PSE fortified milk by oral gavage simultaneously for 13 consecutive weeks.The colon contents of rats were collected carefully for the detection of SCFAs levels using gas chromatography.Results:Overall,the total SCFAs in colon contents of high fat diet group were 33.63% higher than that of the normal control group.High fat diets could significantly increase propionic acid by 126.07% (p<0.05),with a rising trend in acetic acid(26.05%) and isovaleric acid (42.11%) (p>0.05),while showing a downward trend in butyric acid(33.21%) and valeric acid(23.92%) in colon contents (p>0.05).However,PSE interventions could inhibit the increasing levels of SCFAs induced by high fat diets.Low dose of PSE intake could result in an obvious reduction of propionic acid(51.52%), butyric acid(59.59%), valeric acid(72.07%) and isovaleric acid(60.66%) (p<0.05).Similar results could been found in group of high-dose PSE treatment,in which butyric acid was reduced by 29.48% (p>0.05) and levels of acetic acid(48.64%),propionic acid(58.39%),valeric acid(69.12%) and isovaleric acid(58.59%) were significantly decreased(p<0.05).Conclusion:The results indicate that high fat diets could rise the SCFAs levels in colon contents of rats,PSE interventions may adjust intestinal environments through reducing the levels of SCFAs in colon contents.