This study was carried out to determine the effect of adding different ratios of dandelion (Taraxacum offici- nale) extract (KHE) to layer hen rations on performance and egg internal-external quality parameters. In the study, 96 layer Atak-S hens at the age of 22 weeks were used. Chickens were divided into 4 groups, each consisting of six sub- groups, and arranged in a way to have four chickens in each subgroup. The study was conducted over a period of 90 days. During the study, the control group was fed with basal feed, and the experimental groups were fed with feeds with 0.30%, 0.60% and 0.90% KHE added to the basal feed, respectively. Although there was no significant difference between the groups in terms of egg production (P>0.05), it was determined that the average egg production at the end of the study was numerically higher in the groups fed with KHE-containing feeds compared to the control group. There was no significant difference between the groups in terms of feed consumption, feed conversion ratio, live weight, egg yolk colour averages (P>0.05). In the study, it was determined that egg weight in the groups containing 0.90% KHE was significantly higher than the control group (P<0.05). Egg shell thickness were also significantly increased in 0.30% and 0.60% KHE containing groups (P<0.05). It was concluded that dandelion extract has a positive effect on egg quali- ty in laying hens and more studies should be done on this subject.