The effects of Flavomycin, Bacillus licheniformis and Enramycin on broiler performance,nutrient digestibility, gut morphology and the intestinal microflora were studied in a 42-d experiment.A total of 288, one-day-old, male, Arbor Acres broilers were randomly assigned to 1 of 4 dietary treatments (12 pens per treatment with 6 birds per pen).The treatments comprised a control diet without supplementation, a diet supplemented with 5 ppm of Flavomycin, a diet supplemented with the combination of 5 ppm of Flavomycin and 1.35 × 109 CFU/kg B.licheniformis, as well as a diet supplemented with 5 ppm of Enramycin.The average daily gain and feed conversion of birds fed the diet with Flavomycin combined with B.licheniformis and the Enramycin diet were improved over the entire experiment compared with the control diet.The digestibility of dry matter, energy, phosphorous and calcium for birds fed the Flavomycin and B.licheniformis diet and the Enramycin diet were enhanced.All additives improved the villus height and crypt depth in the duodenum, jejunum and ileum on d 21.In addition, reduced numbers of cecal E.coli were found in birds fed all three supplemented diets on d 42.In conclusion, supplementation with Flavomycin and B.licheniformis or Enramycin appeared to be superior to supplementation with Flavomycin alone.All three additives were superior to the control.