Marigold (Tagetes erecta L.) was reported to be a good source of xanthophylls [6, 7] and used for pigmentation of the egg yolks and poultry skin [12, 13]. Recently, it was shown that inclusion of 40 g kg−1 of marigold flour in the diet of laying pullets did not reduce external quality of eggs and there were no effects on body weight, hen day egg production, egg weight, or feed conversion rate [14]. The findings of the present study on body weight, hen egg production, and feed consumption are in agreement with those reported in the previous studies [10, 14]. However, in the present study inclusion of 20 g kg−1 marigold flour into the diets caused a decrease in egg size compared to the control for an unknown reason