The recent development of antibiotics-resistant pathogens in poultry, which poses a threat to human health, has necessitated the search for an alternative to antibiotic growth promoters (AGPs) to improve the gut microflora in poultry diets. One of the alternatives to AGPs is probiotics which are beneficial organisms. The by-products of the digestion of polysaccharides for which poultry do not have enzymes to digest are called prebiotics. Prebiotics serve as food for probiotics. The application of enzymes makes this digestion possible. The prebiotic potentials of enzyme supplemented high fibre feedstuffs (HFFs) are not known. This study was conducted to assess the prebiotic potential of xylanase enzyme supplemented wheat offal on broiler chickens (in-vivo). The replacement of maize with wheat offal irrespective of levels supplemented with 100ppm xylanase enzyme caused a reduction in feed intake and an increase in weight gain and better feed conversion ratio. Birds fed diet with 20% wheat offal supplemented with a xylanaseenzyme outperformed birds fed diets with 10 or 30% wheat offal supplemented with a xylanaseenzyme and birds fed the control diet. The birds had normal weights of vital organs with good structural consistency. The identification of microbes (fungi and bacteria) showed that dietary levels of wheat offal (10, 20 or 30% inclusion) with supplementation of a xylanase enzyme enhanced the growth of beneficial microbes, which resulted in the inhibition or elimination of the opportunistic/pathogenic microbes. It was concluded that enzyme supplementation of high fibre feedstuffs could improve the growth performance, nutrient retention and increase concentration of beneficial microbes in the guts. The use of enzymes is therefore recommended when HFFs are required as a prebiotic source in the guts of broilers.