The subtropical humid region of Brazil is characterized by a minimum of 60 mm monthly rainfall. This rainfall characteristic induces soil degradation as a result of the frequency in which the soil is kept above friability, mainly during the crop establishment period, even under no-till system. After 30 years of no-till system adoption, are observed, in this region, crop failures due to dry spells. This problem is associated to physical soil degradation of the subsurface layer, denoted by increase in soil density and resistance to penetration besides reduction in soil permeability, characterized as soil compaction. Actions to mitigate soil compaction have oriented studies towards vegetative practices. The present study was developed to evaluate the effect of the consortium maize-brachiaria (Brachiaria brizantha) on the mitigation of soil compaction by altering the soil physical parameters, development of maize and brachiaria roots, and grain yield of maize and brachiaria biomass. A trial with two treatments, single maize and maize consortiated with brachiaria, with four replicates, in a Dark Red dystrophic Latosol, in Coxilha, RS, was conducted from 2005/2006 to 2007/2008. Three soil layers were evaluated for root biomass of maize and for maize plus brachiaria, and physical and chemical soil parameters, besides grain yield of maize and biomass of brachiaria. The results showed that the consortium maize-brachiaria, although the biomass of roots has been increased without altering the maize grain yield, was not efficient in mitigating soil compaction.