The black cumin (Nigella sativa) (NS), the member of Ranunculacea family, is a plant widely used as a spice in our country. Its seed oil contains 21% protein, 35% carbohydrate, 35-38% lipid. The aims of this study were to investigate if the proinflammatory cytokines generated in trinitrobenzene sulphonic acid (TNBS)-induced colitis affect the gastric tissue and to determine the effects of orally administered NS seed oil (ORIGO '100% naturel Black Cumin Seed Oil', 2.5 ml/kg; orally) on the gastric tissue. Rats were grouped as control (n=5), NS treated control (n=5), colitis (n=6) and NS treated colitis (n=7). NS was given 5 minutes later than the induction of colitis and the treatment was continued for 3 days. Three days after the induction of colitis, all rats were decapitated and gastric tissues were removed and homogenized. Total sialic acid (SA), glutathione (GSH), malondialdehyde (MDA) levels; catalase (CAT), superoxide dismutase (SOD) activities were measured in the homogenates. Gastric tissue samples were also examined cytologically. TNF-a, IL-1b and IL-6 and LDH levels were determined in blood samples. In the NS treated control group SA levels were significantly decreased when compared with the control group. In the colitis group increased plasma proinflammatory cytokines and decreased tissue CAT, MDA and SA levels suggest that activation of immun system protects the gastric tissues. On the other hand in the NS treated colitis group, significantly increased gastric tissue CAT activity compared with the colitis group indicate that thymoquinone content of black cumin has SOD like activity. Therefore, black cumin seed oil may have protective effects on gastric tissue.