Mulching (crushing capoeira) is an alternative system for the use of fire for cultivation in the Northern region of Brazil. Cowpea is c onsidered an important food crop in this region; however, weeds might limit its productivity. This study aimed to evaluate the population dynamics of weeds and the productivity of cowpea with different habit of growth inoculated with Bradyrhizobium sp in m ulching. The experiment was carried out in randomized blocks with the cultivars BRS Guariba and BR 17 Gurgueia, w ith and without inoculation of Bradyrhizobium sp and nitrogen fertilization as a control. Twenty seven species and three genera of weeds were i dentified, distributed into 12 botanical families in the BRS Guariba cultivar and 25 species in ten families in B R 17 Gurgueia cultivar. The results revealed that the significative species were Vismia guianensis (Aubl.) Cyperus sp, Scleria melaleuca Rchb. ex Schltdl. & Cham, and Spermacoce verticillata L. Inoculation with Bradyrhizobium sp reduced the infestati on of the most important species and presented higher productivity (1965.09 kg ha 1 ) than the treatment without inoculation (987.14 kg ha 1 T he growth habit of cowpea cultivars in mulching (crushing capoeira) system did not affect crop yield, but longer studies are needed to validate the information obtained