Winter cover crops are grown on two million ha of the grain production area under no-tillage (NT) management in the state of Rio Grande do Sul in southern Brazil. The primary cover crops are Avena and Lolium species, which could provide forage for grazing ruminants in the winter, providing agricultural diversification through integration of grain and livestock production. Many farmers are hesitant to integrate livestock and crops in this manner because of fears that grazing animals will cause excessive soil compaction on cropland. Poor grazing management on winter cover crops can indeed result in detrimental effects on the establishment and yield of subsequent grain crops. Our objective was to evaluate alterations in soil bulk density, macroporosity, microporosity, and compressibility of soil due to animal treading resulting from different grazing pressures. The experiment has been conducted since 2001 on a Rhodic Hapludox soil that has been under NT for 12 years. The experimental area (23 ha) was divided into 12 paddocks distributed within 3 replicates. The treatments consisted of different pasture sward heights during the winter: 10, 20, 30 and 40 cm maintained by use of variable continuous stocking of cattle (put-and-take), and a non-grazed treatment. Soil samples were collected after the third year of winter grazing (November 2003) from depths of 0-2.5, 2.5-5.0, and 5.0-10.0 cm for soil porosity and bulk density measurements, and from 2.5-5.0, 7.5-10.0, and 12.5-15.0 cm for measuring preconsolidation pressure (σ_p) of the soil. There was no effect of grazing treatments on density, porosity, and preconsolidation pressure of the soil when compared with the non-grazed treatment. Moreover, the presence of grazing cattle did not alter soil physical properties when compared with measurements taken prior to entry of cattle into the experimental area.