Thyme (Thymus vulgaris L.) is medicinal plant in the lamiaceae family which is cultivated worldwide for cosmetic, culinary and medical uses. The current study aimed to investigate the impact of thyme on the nutritional parameters of obese rats. Phenolic and flavonoid components were detected in dry thyme powder by HPLC-UV and thyme essential oil was analyzed by GC-MS. In the biological experiment, the study included 30 male rats of weight approximately 200 grams which were divided into 5 groups; each group comprising 6 rats. Group (G1) rats were fed on basal diet, serving as a negative control group (N-control), while group (G2) rats were fed on a high-fat diet (fat percentage 15%) (P-control).The same diet used in (G2) was given to group (G3) but along with orlistat supplementation (2mg/Kg BW rat/day) using a stomach tube. Similarly, the rats of groups (G4 and G5) received HFD and supplemented with thyme powder (3g/100g diet) and thyme essential oil (0.6g/100g fat), respectively. The obtained results indicated that, dry thyme powder composition included high concentration of phenolic compounds such as ellagic acid and salicylic acid, as well as high concentration of flavonoids was hesperidin. The major constituent of thyme essential oil was thymol. After 8 weeks, the rats fed on HFD and supplemented with different treatments (G3, G4, and G5) showed a significant decrement in glucose levels. In addition, the treatments also showed significantly enhanced lipid profiles, liver functions, and total antioxidant capacity. However, the activities of catalase and glutathione reduced were significantly elevated in the blood of thyme powder and essential oil-treated groups. Moreover, malondialdehyde was significantly decreased in the treated groups. The induction of redox enzymes serves as a dependable marker for assessing the antiperoxidative effect of herbs; hence, this study revealed the role of thyme powder and essential oil treatment in the reduction of histopathological and liver abnormalities associated with obesity.