Vernonia mespilifolia is widely used in folk medicine in the Eastern Cape Province, South Africa. The aim of this study was to evaluate the biological activity of the acetone, aqueous and ethanol extracts of Vernonia mespilifolia using brine shrimp hatchability and lethality assay. The result showed hatching success in this order: aqueous extract (48.6%) > acetone extract (38.2%) > ethanol extract (26.8%). The LC₅₀ of the lethality assay were in this order: acetone extract (67.8 µg/mL) > aqueous extract (132 µg/mL) > ethanol extract (383 µg/mL). According to Meyer’s toxicity index (using brine shrimps), LC₅₀ < 1000 µg/ mL is toxic. Therefore, the results of the three solvent extracts could be said to be toxic as do have LC₅₀ < 1000 µg/ mL. However, the toxicity of the crude extracts could suggest or confer some antitumor properties, hence further in vitro, in vivo and antitumour assays are recommended to further substantiate these claims.