Abstract: This study investigated the effect of a crude Hydroalcoholic Extract (HE) obtained from aerial parts of Bidens pilosa L. on in vitro and in vivo leukocyte mobilization, using models of chemotaxis and pleurisy induction by carrageenan in rats, respectively. Leukocytes treated with 100 and 200 g mL-1 of HE had a reduction of chemotaxis in 35.5 and 52.2%. Rats treated orally at dose of 250 mg kg-1 showed 60.5% reduction of total cells in pleural exudate. HE induced reduction of leukocyte mobilization in both in vitro and in vivo assays, which suggests a potential anti-inflammatory effect.