Poly(vinyl alcohol) (PVA)/pig manure compost composite beads proved suitable as a biofilter material in a biofiltration process. The composite bead is a porous spherical particle with a diameter between 2.4 and 6.0 mm and a density of 0.96 g cm(-3). It contains 9.43 mg P g(-1) dry solid and 12.1 mg N g(-1) dry solid. The equilibrium moisture contents of the PVA/compost composite beads bed for adsorption and holding experiments are 50.5% and 54.6% by wet basis, respectively, which correspond to the optimal filter material required and could sustain the biological activity. The PVA/pig manure compost composite beads bed has higher moisture-holding capacity and compression strength than the pig manure compost bed. The PVA/compost composite beads have buffer capacity and could keep the filter bed at pH 6.9-7.2 during operating. The percentage of ethyl acetate removed could stay at over 99% for 40 days of operation as the PVA/pig manure compost composite beads adsorbed inorganic nitrate nutrient. The maximum elimination capacity of the PVA/pig manure compost composite beads filters at the loading rate of 0.71 kg ethyl acetate m(-3)-bed h(-1) is 0.71 kg ethyl acetate m(-3)-bed h(-1). (c) 2005 Society of Chemical Industry