Japanese barberry or ornamental barberry (Berberis thunbergii) belongs to the Berberidaceae family. This family have several properties, including antioxidant, antimicrobial and anticancer activities. The healing properties of barberry have been known and studied for thousands of years. In order to study the changes in the physiological-biochemical characteristics of Japanese barberry under the influence of abiotic elicitors, an experiment was conducted in the form of a completely randomized design in the greenhouse and laboratory of the Faculty of Agriculture and Natural Resources of Imam Khomeini International University in 2018-2019. The treatments included methyl jasmonate elicitors, salicylic acid, titanium dioxide and no elicitor (control) in four replications. In this research, the amount of leaf photosynthetic pigments and antioxidant enzymes of leaf and root tissues of Japanese barberry plant were extracted and measured. The results showed that the effect of the experimental treatments on the amount of photosynthetic leaf pigments and antioxidant enzymes in the two studied tissues was significant at the 1% probability level. Comparison of the means showed that salicylic acid treatment increased the amount of chlorophyll a and total leaf chlorophyll compared to the control by 20.9% and 21.3%, respectively. Salicylic acid and methyl jasmonate increased 29.9 and 19.1 percent of carotenoid content in leaves, respectively, compared to the control. The highest protein content of the root was produced with the use of salicylic acid, which increased by 38.6% compared to the control. The activity of catalase enzyme in the root increased by salicylic acid and titanium dioxide elicitors by 76.8 and 52.2%, respectively, compared to the control. In leaves, salicylic acid and methyl jasmonate elicitors increased catalase enzyme activity by 104.1% and 57.1%, respectively. From this research, it was concluded that salicylic acid had the greatest effect in increasing the amount of pigments and the activity of antioxidant enzymes of the Japanese barberry plant, which can be used for medicinal products.