The effect of stocking rate on pasture and animal production responses to ammonium nitrate fertilizer, applied at nil, 134, 336 and 672 kg N/ha/annum, was measured from kikuyu (Pennisetum clandestinum) based pasture on a basaltic derived kraznozem at Wollongbar on the north coast of New South Wales. The continuous stocking rates of yearling Angus cattle, which ranged from 2.2 to 16.6 animals/ha, were originally designed to utilize 40, 60 and 90% of the annual pasture growth at each level of N. The study reported the effects of the treatments over the first two years of the experiment.The nitrogen requirement of the pasture, measured by the dry-matter response to additional N applied at 350 kg/ ha in temporarily caged areas, was not affected by increased stocking rate at nil, 134 and 336 kg N/ha/annum. Over these rates of annual nitrogen application, each at a low and high rate of stocking, similar responses to additional nitrogen were measured two months after nitrogen fertilizer was applied. Increased stocking rates improved the N content of the pasture and the proportion of N in leaf material, altered sward structure and reduced presentation yields of dry-matter and N in leaf, stem and litter components of the sward. Increased stocking rates prevented the immobilisation of large quantities of N in the litter fraction of the sward. Weight of underground organs was not significantly affected by stocking rate.Absolute growth rate of the pasture increased linearly from 37 kg/ha/day to 84 kg/ha/day at the nil and 336 kg N/ha treatments respectively. Over this range of N fertilizer application, the response to additional N was similar, although N stress was apparently reduced from 62 to 39 percent. N concentration of leaf, stem, litter, rhizome and root responded linearly to the highest rate of N. Fertilizer N increased dry-matter yield of leaf, stem and at certain times, the rhizome fraction but not litter or root fractions. The N yield response of each component was curvilinear over the range of N rates tested with the point of inflection occurring at the 336 kg N/ha treatment. Rate of live-weight gain per head was negatively and linearly related to increased stocking rate, at each level of N application. The following regression coefficients were established for annual live-weight gain per head (y) on stocking rate (x) for each level of N .................................