Aim: In this study, it was aimed to investigate the effects of beta glucan (BG) on the experimental colitis model created by using trinitrobenzene sulfonic acid (TNBS). Material and Methods: Thirty-two Wistar Albino rats were divided equally into four groups as sham control, TNBS, TNBS-BG3, and TNBS-BG10 groups. While saline was administrated to sham group, TNBS was administered intrarectally to the TNBS groups under anesthesia. BG was administered at a dose of 100 mg/kg by oral gavage, intragastrically, for 3 days (TNBS+3) to the TNBS-BG3 group and for 10 days (7+TNBS+3) to the TNBS-BG10 group. At the end of the study, macroscopic, histological and biochemical tests were applied to the colon tissues taken. Results: It was determined by histopathological scoring and biochemical results that BG administration caused positive effects on colon damage due to colitis. Malondialdehyde level and myeloperoxidase activity were found to be significantly higher in the TNBS group compared to the other groups (p=0.003 and p<0.001, respectively). Antioxidant levels increased in BG treated groups compared to TNBS group. While this increase was statistically significant among glutathione levels (p<0.001), it was not statistically significant in catalase enzyme activity (p=0.218). BG administration reduced the increase in lipid peroxidation and leukocyte infiltration level in the colon tissue. Positive changes due to the prophylactic effect of BG were determined in histological and biochemical results. Conclusion: BG administration has been found to show anti-inflammatory and antioxidant properties, and BG has a treatment potential in reducing colon tissue damage due to TNBS-induced colitis.