Sophocapine, matrine, oxymatrine, sophramine, aloperine, cytisine, N-methylcytisine, lehmannine and the total alkaloids of the plant were respectively used to add in the PDA medium, the alkaloid concentration in which was 1×10-4g/mL. Then Botrytis ceneria was cultured in the media, on which the pine wood nematodes (Bursaphelenchus xylophilus) was cultured. The reproduction of the nematode on the medium was observed and recorded. The results indicated that high inhibitory effects were observed in the treatments of aloperine, cytosine and total alkaloids, among which aloperine could not only completely inhibit reproduction, but also cause mortality of the nematode. The analysis of the activity of the tested alkaloids on the pine wood nematodes and their molecular structures demonstrated the hypothesis on relationship between activity of the quiniolizidine alkaloids on pine wood nematode and their functional group pairs (FGP) in the molecular.