Aim of study: This study evaluated the impact of thyme (Thymus vulgaris L.) essential oil (TEO) supplementation on performance, egg quality, and serum and faecal mineral composition in chukar partridges (Alectoris chukar). Area of study: Türkiye. Material and methods: Ninety-layer partridges, aged 32 weeks, were randomly assigned to five groups. Within each group, there were six replicates with three birds/replicate. The experimental design included a control group receiving a basal diet (0 mg/kg TEO) and four treatment groups with diets supplemented with TEO at 50, 100, 150, and 200 mg/kg over 56 days. Main results: The results showed no significant differences in performance parameters among the groups (p>0.05). However, egg production and mass were significantly higher in the 50 mg/kg TEO group than in the control group (p<0.01). Additionally, eggshell thickness and yolk index were improved in the 50 mg/kg group compared to the 100 mg/kg group (p<0.05). Serum and faecal mineral compositions did not differ significantly among the experimental groups (p>0.05). Research highlights: These results suggest that incorporating TEO at 50 mg/kg into the diet of chukar partridges may be optimal, as higher concentrations could potentially interfere with nutrient absorption and negatively affect partridge attributes. Nevertheless, further research is needed to elucidate the mechanisms of action of TEO´s active ingredients in partridge feed.