Cymbopogon citratus Stapf (DC) (Lemongrass) is a widely distributed aromatic perennial plant that has the potential to mitigate xenobiotic-induced systemic disorders. However, whether C. citratus has any ameliorative effect on gasoline vapour (GV)-induced thyroid gland dysfunction has not been previously evaluated. Therefore, the present study aimed to assess the effect of C. citratus leaf decoctions on GV-induced thyroid gland disorders. Thirty-five Albino rats were segregated into 5 groups (n=7 per group). Animals in group 1 served as unexposed control, while animals in group 2 were exposed to GV alone for 4 weeks. Animals in groups 3, 4 and 5 in addition to being exposed to GV for 4 weeks, were treated with different concentrations of C. citratus leaf extracts for 2 weeks. Animals exposed to GV alone had significant decrease in serum levels of catalase, while serum levels of malondialdehyde significantly (p <0.05) increased. Serum levels of thyroid stimulating hormone significantly (p <0.05) increased and decreased in male and female rats respectively exposed to GV alone. Serum levels of triiodothyronine decreased in both male and female rats exposed to GV alone, whereas serum levels of thyroxine decreased only in female rats. In addition, exposure to GV alone caused significant alterations in the normal histo-morphology of the thyroid gland. Co-administration of C. citratus leaf decoctions caused reversal of these changes, as well. This study showed that C. citratus leaf extract has the potential to attenuate GV-induced thyroid gland disorders and oxidative stress due to its natural bioactive constituents. Manuscript profile