In this work, 5 alkaloids: sanguinarine, cryptopine, β-allocryptopine, protopine and 6-methoxyl-dihydro-chelerythrine were isolated by an activity-guided isolation protocol from Macleaya microcarpa (Maxim) Fedde, and their novel anthelmintic efficacy to Dactylogyrus intermedius in goldfish (Carassius auratus) was firstly found and investigated.Initially 5 extracts were prepared with different solvents and the ethanol was selected because it was the most active in anthelmintic tests.After that, the extract of M.microcarpa obtained by extracted with ethanol was subjected to activity-guided isolation to get five active alkaloids.