Dengue virus (DENV) is a member of the Flaviviridae family and is responsible for the most common mosquito-borne human disease. Currently, there are no available antiviral drugs to treat DENV infections. However, certain flavonoids, including baicalein and baicalin, have demon-strated significant anti-DENV effects in vitro. This study aimed to assess the bioavailability of baicalein and its metabolite, baicalin, in the blood serum of Albino Wistar rats using the LC/MS/MS method. The in vitro activity of sera obtained from rats administered baicalein was evaluated for its anti-DENV properties using quantitative RT-PCR and the Foci Forming Reduction Assay (FFRA). The results obtained through LC/MS/MS analysis indicated that the bioavailability of baicalin in rat blood serum reached 44.20 µg/ml one hour after oral administration of baicalein. Furthermore, the sera collected from rats given baicalein exhibited a significant 78.26% inhibition of DENV-2 replication when tested against Dengue-2 using both quantitative RT-PCR and FFRA. These findings suggest that baicalein and baicalin hold promise as potential therapeutic candidates for further investigation in the development of treatments against DENV infections.