Objective To explore the effect and mechanism of glutamine to the aberrant crypt foci (ACF) in rat injured by acetic acid. Methods Thirty Wistar rats were averagely divided into three groups: control group, acetic acid group and glutamine group. The colon of the rat was infused with 1% acetic acid. Started to gavage with glutamate two days after modeling glutamine group. The injured colons were studied after fourteen days with light and scanning electronic microscope. Paraffin sections of specimens were prepared and stained with HE. The colon crypts were isolated by HCl digestion method. The expressions of CD44 and ICAM-1 in the epithelial cell of the large intestine mucosa were detected by immunohistochemistry method. Results On the days of 14， the number of ACF in the glutamine group were remarkably decreased as compared with that of the acetic acid group and a branch-like. The expressions of ICAM-1 and CD44 (every 1 000 cells) were 302.1±30.1 and 298.6±28.3 in glutamine group, 223.6±23.5 and 221.5±28.6 in control group, 198.5±19.5 and 215.3±17.8 in acetic acid group, respectively. While the expressions of CD44 and ICAM-1 in intestine were increased remarkably in the glutamine group compared with the control group and acetic acid group (P＜0.05). Conclusion Glutamine could decrease the formation of the ACF injured by acetic acid. Increasing the expressions of CD44 and ICAM-1 may be one of the important factors to decrease the ACF.