The aim of the three-year experiment was to evaluate the impact of Starane 250 EC herbicide and different levels of nitrogen fertilization on the yield of dry matter and crude fibre content in meadow sward. The field experiment was established on a permanent meadow in April 2007, in Żelków, in the system of randomised blocks with three replications. In the experiment, two research factors were used. The first experimental factor was varied fertilization (34% ammonium nitrate) applied in amounts of A₁ – 0 kg ha^-1, A₂ – 90 kg ha^-1, A₃ – 180 kg ha^-1 and A₄ – 270 kg ha^-1. The second research factor was Starane 250 EC herbicide, applied at four concentrations (B₁ – 0 dose, B₂ – 0.5 dose, B₃ –1 dose as a norm, B₄ – 1.5 the dose of the norm). Detailed study included yield of plant dry matter and crude fibre content in the meadow sward. The results were evaluated statistically by using analysis of variance for two-factor experiments. Mean differences were verified by Tukey's test at significance level p ≤ 0.05. The highest yields were obtained on the objects where the highest dose of nitrogen fertilizer was applied without any concentration of the herbicide. The crude fibre content in the tested plant material ranged from 20.88% to 28.79%, indicating that the feed obtained from the experimental plants does not exceed the limit values necessary for the nutrition of ruminants.