This study aims to evaluate the allelopathic activity of Bambusa vulgaris Schrad. ex J.C. Wendl., invasive species in an area of Cerrado in the Chapada do Araripe in Ceará. The treatments consisted of the aqueous extract in concentrations of 25, 50, 75 and 100% and a Control (distilled water), with five replicates containing 20 seeds each. The tests were carried out in the laboratory and in a greenhouse, using corn and beans as the test seeds. The parameters analyzed were number of germinated seeds, measurement of caulicle and radical length, occurrence of radicle necrosis and germination speed index (GSI). The results obtained from the laboratory bioassays on corn seeds indicate that the extract affected development of the seedlings, reducing caulicle growth and increasing radicle length, in addition to causing radicle necrosis. Regarding the bean seeds, there was a delay in the GSI, reduced caulicle growth and radicle necrosis. In the bioassay conducted in the greenhouse, for the corn seeds the extract inhibited germination and both caulicle and radicle growth, as well as delaying the GSI. When tested on the beans, the extract provoked reduction in the number of germinated seeds at the higher concentrations, delayed the GSI, reduced the radicle size and caused radicle necrosis. The allelopathic effects observed in the greenhouse were more significant, suggesting that environmental factors in conjunction with the action of the allelochemicals interfered more actively with the seed germination and seedling development of the receptor species.