The use of winter cover crops is an important practice for the management and conservation of soil and water in southern Brazil. The objective of this work was to evaluate the accumulation of green mass and dry mass in the aerial part of winter cover crops in monocropping and intercropping in southwestern Paraná, in the years 2016 and 2017. Randomized blocks were used as experimental design with a subdivided plot scheme of 50 m² with five replications. The cover crops used in monocropping were black oats and wheat, while for the intercropping black oats + turnips + rye + white lupin (AP+NF+C+TB), black oats + turnips (AP+NF) and black oats + turnips + rye + vetches + white lupin + buckwheat (AP+NF+C+E+TB+TM) were used. The data were subjected to analysis of variance and the means were compared by the Tukey test at 5 % probability. The intercrop composed of black oats + turnips + rye + vetches + white lupin + buckwheat had a higher production of green mass, with an average value of 50.880 kg ha^-1. For the production of dry mass, the monocrop of black oats had higher yields, with an average value of 5.168 kg ha^-1. The highest yields were obtained in the coverage area with black oats, turnips, rye, vetches, white lupin and buckwheat, presenting a yield in 2017 of 4.487 kg ha^-1.