1. This research was conducted to determine the effect of diet supplementation with Echinacea extract (cichoric acid) on the growth performance, antibody titres and intestinal tissue histology of layer chicks. White, 1-d-old, Hy-Line hybrid chicks (n = 540) were divided into three treatments, each consisting of 6 groups of 30 chicks (n = 180): (1) control; (2) 2-5 mg/kg cichoric-acid-fed; and (3) 5mg/kg cichoric-acid-fed. The trial lasted 60 d. While the growth performance of the chicks was depressed between d 1 and 45, it was found to improve between d 45 and 60. Feed consumption was lower in both of the cichoric-acid-fed groups than in the control group between d 1-15 and 15-30, but was higher between d 30 and 45. Overall, mean feed consumption did not differ between the control and cichoric-acid-fed groups during the 60 d study period. During the 60 d evaluation period, live weight gain, feed utilisation rate and final live weight were higher in the control group than in both of the cichoric-acid-fed groups. Antibody titres against infectious bronchitis and infectious bursal disease did not differ between the three groups, but those for Newcastle disease were higher in the 2-5 mg/kg cichoric-acid-fed group than in the control group after 45 d. Height and width of thejejunal villus and the thickness of the muscle layer were lower in the 5 mg/kg cichoric-acid-fed group than in both the control and the 2-5 mg/kg cichoric-acid-fed groups. The height of the ileal villus was also lower in the 5 mg/kg cichoric-acid-fed group than in the other two groups. Echinacea extract supplementation for layer chicks appears not to benefit growth performance and intestinal histology during the growing period. © 2010 British Poultry Science Ltd.