en Nervous system (others) Others Experimental research article Experimental research article Introduction: Origanum vulgare a rich source of natural phenolic antioxidants and has potential to be a source nutritional ingredients for functional food. Herbs such as Origanum have long been used in food preservation d in traditional medicine in the treatment of common ailments and have potential for positive modulation oxidation-linked diseases such as diabetes. Here we investigated the effect of aqueous extract of Origanum aves, stems and flowers) on spatial learning. Methods: After scientific identification, the leaves were used for extraction. 35 adult NMRI male rats weighing 0-350 gr were utilized in 5 groups. Control group (no injection), the second group (saline injected), the extracts h different doses (150, 300, 450) mg/kg were injected intraperitoneally to experimental animals. All animals re trained for a spatial learning task using T-maze and were then trained subsequently daily based on standard thod. Results: Statistic analysis ANOVA showed that Origanum aqueous extract significantly decreased the number learning and error in simple and reverse learning (p<0.05) and it had no significant effect on delay time in both e of learning. Conclusion: It can be concluded that the effect of Origanum extract on learning can be due to its antioxidant d presence of anti acetylcholine estrase compounds such as ursolic acid. Medicinal plant; Origanum vulgare; Spatial learning; T-maze. 143 150 http://ppj.phypha.ir/browse.php?a_code=A-10-88-1&slc_lang=en&sid=1 Mehdi Abbasnejad mabbas@mail.uk.ac.ir 320031947532846002925 320031947532846002925 Yes Mansour Mirtajadini 320031947532846002926 320031947532846002926 No Mohammad Reza Afarinesh 320031947532846002927 320031947532846002927 No Neda Hassibi 320031947532846002928 320031947532846002928 No