The presence of weeds in agricultural crops causes direct losses in productivity, causing economic losses, which makes it necessary to know the quality and quantity of weeds that compete with agriculture crops. Therefore, the objective of this work was to identify the weed community associated with cassava cultivation through a phytosociological survey, carried out in a cassava cultivation area, in the city of Nampula. The frequency, density and absolute and relative dominance, and the importance value index were analyzed. A total of 196 individuals were identified, distributed in 15 families and 27 species, with greater emphasis on Asteraceae followed by the Poaceae family. The most important specie was Amaranthus deflexus.

Keywords: Manihot esculenta L., competition, importance value index, phytosociology.