The healing properties of hemp agrimony (Eupatorium cannabinum L.) have been already described in the seventeenth-century Polish medical herbaria. These historical descriptions also pointed to their potential anticancer activity. Contemporary literature data confirm the presence of many bioactive compounds in hemp agrimony, but there are few data confirming their anti-cancer properties. Phytotherapy is used as a form of natural treatment or supporting conventional methods of therapy of many diseases. Supplementation with herbal preparations is currently very popular, which is why it seems important to study the anti-cancer potential of these plants. Aqueous extract: 10 g of dried aerial part of plants was extracted in water at temp. 80*C for 3h and filtered, evaporated, and reconstituted in water to a final stock solution (100 mg/mL). Cytotoxicity assay: The effects of plant extracts on cell growth were determined by incubating cells with different concentrations for 72 h at 37°C in standard 96-well plates. The cell growth inhibition was determined by MTT reduction assay (spectrophotometric analysis). The aqueous extract showed a cytotoxic effect against U87 MG with IC₅₀ values of 0,09±0,01 μg/mL. The plant revealed high total phenolic content, total flavonoid, and antioxidant capacity. The synergistic effect of bioactive compounds of hemp agrimony plausibly contributed to the cytotoxic effect of the extract. The presented results suggest that the historical description of the anti-cancer properties of hemp agrimony may have scientific justification and be the starting point for further research.