Chikungunya (CHIKV) and Zika (ZIKV) viruses are two arboviruses which have recently broken their sylvatic isolation and gone into a rampant spreading among humans in some urban areas of the world, specially in Latin America. Given the huge burden that Chikungunya and Zika fevers impose to public health in the affected countries and the lack of effective interventions against them, the aim of this work was to evaluate the antiviral potential of bovine lactoferrin (bLf) - an iron-binding glycoprotein with broad-spectrum antimicrobial properties - in both CHIKV and ZIKV infections. The general antiviral activity of bLf was assessed by plaque assays, and the inhibitory effects of the protein on specific stages of virus infecion was evaluated by immunofluorescence and nucleic acid quantification assays. Our data show that bLf exerts a dose-dependent strong inhibitory effect on the infection of Vero cells by the aforementioned arboviruses, reducing their infection efficiency in up to nearly 80%, with no significant cytotoxicity, and such antiviral activity occurs at the levels of binding and replication of the virus particles. Taken together, these findings reveal that bLf antimicrobial properties are extendable to CHIKV and ZIKV, underlining a generic inhibition mechanism that can be explored to develop a potential strategy against their infections.