Several individual alfalfa (Medicago sativa L) root saponins were tested for their haemolytic activities using two methods, namely the haemolytic index test and a haemolytic micromethod. It was shown that individual saponins gave different haemolytic activities depending on their structure and also on the haemolytic test used. Generally it was found that saponin monodesmosides were more active than their bisdesmosidic analogues. These differences in haemolytic activities may strongly influence the results of saponin determination with haemolysis-based methods.