In the present study, chicory root powder (CRP) as growth promoter at 1% and 3% levels was supplemented in broilers’ diet to investigate the growth performance and histo-morphometry of jejunum. One hundred twenty, one-day-old male broilers were used in a completely randomized design (CRD) with 3 treatments and 4 replicates (10 chicks per replicate). At the end of each period (0-10, 11-24 and 0-24 days), feed intake (FI), weight gain (WG), and feed conversion ratio (FCR) were measured. At the end of experiment (day 24), one bird per replicate was sacrificed for breast weight (BW), drumstick weight (DW), and jejunum length (JL) as a percentage of body weight, and histomorphometry of villus. The FI increased by 3% CRP in the 1^st period (p < 0.01). The percentage of WG significantly increased at 1% during the 1^st period and, in the 2^nd and total periods, it increased only at 3% CRP (p < 0.05). The FCR decreased at 1% in the 1^st (p < 0.04) and, at 3% in the 2^nd (p < 0.01) and total periods (p < 0.05). The percentage of DW increased at 3% CRP (p < 0.05). The treatments increased the percentage of BW (p < 0.059) and, percentage of JL (p < 0.079) as well. The villus width and, crypt depth (CD) at 1% and 3% CRP and, villus surface at 3% reduced. The 3% CRP increased the villus length (VL) and villi number (p < 0.05) and, VL/CD (p < 0.01) and, villus surface area (p < 0.02). The percentage of leaf-like villi decreased in CRP treatments (p < 0.05). The number of goblet cells increased in CRP treatments (p < 0.01). In conclusion, chicory root powder can improve growth performance in broilers by enhancing food digestion and absorption through modification of jejunum histomorphometry.