A series of novel indole-2-carboxylate derivatives were synthesized and assayed to determine their in vitro broad-spectrum antiviral activities. The biological results showed that some of the synthesized compounds exhibited potent broad-spectrum antiviral activity. Notably, compound 8f showed the highest SI value (17.1) to Cox B3 virus. Compound 14f showed both potent inhibitory activity against influenza A (IC50=7.53 μmol/L) and the highest SI value (12.1). SAR results showed that the alkyloxy at the 4-position of indole ring was not crucial to the antiviral activities. Incorporation of an acetyl substituent at the amino group disfavored antiviral activity towards RNA viruses.