This study was conducted to evaluate growth performance and ileal microflora in response to sugar cane bagasse (lignocellulose) and corn particle size. Three hundred and thirty six Ross 308 male broilers were assigned in a 2 × 2 factorial arrangement of treatments with 2 particle sizes (coarse and fine) and 2 levels of a lignocellulose (0%, 2%). Each treatment had 6 replicate pens of 14 birds from 0-24 d. Feed conversion ratio (FCR), weight gain and feed intake were measured from 0-10 and 10-24 d.