Abstract: The aim of the present study was directed to investigate the therapeutic efficacy of intraperitoneally injected curcumin as anticarcinogenic treatment modality on 7,12-dimethylbenz[a]anthracene (DMBA) induced hamster buccal pouch(s) (HBP(s)) carcinoma. Subjects and methods: Thirty Syrian male hamsters, five weeks old, weighing 90-130g were divided into three group(s) (G(s)): A, B, and C. G-A (negative control): HBP mucosa of 10 animals were painted with liquid paraffin alone three times a week for 14 weeks. G-B (positive control): 10 animals were painted with 0.5% DMBA in paraffin oil 3 times a week for 14 weeks. Then animals were left untreated for 6 weeks after DMBA painting. G-C (curcumin treated group): 10 animals were injected intraperitoneally with curcumin 80 mg/kg body weight every day for 6 weeks following DMBA-treatment. The assessment was based on the gross observation, histological and immunohistochemical examination utilizing anti-apoptotic Bcl-2 antibody. Results: Gross observation revealed variation in reduction of the tumor size in the treated group (G-C) compared to that observed in group G-B. Histopathological findings revealed variations between G-B and G-C groups. Immunohistochemical results revealed that Bcl-2 expression has a variability in the area % throughout the groups used. Groups G-A, G-B, and G-C were 7.78%, 75.51%, and 41.65% respectively. Conclusion: The therapeutic effect of intraperitoneally injected curcumin resulted in promising outcome in regression of DMBA induced HBP carcinoma.