In a previous work we evaluated the effects of Silymarin, a natural antioxidant and hepatoprotective polyphenolic compound, on laying hens performances and health status. The aim of the present work was to further confirm the previous results and to investigate the effects of Silymarin on ovarian endocrine activity and productivity of laying hens as well as on egg traits. Eighteen laying hens were randomly allotted into 3 groups and observed for 20 weeks: control hens were fed control diet, while treated groups received supplementations of 200 (S200) and 400 (S400) ppm of Silymarin. S200 group showed improved eggs laying rate (+2.91%), feed conversion rate (-4.52%) and a significant (P