Plant essential oils from 43 plant species were tested for their nematicidal activities against the pine wood nematode, Bursaphelenchus xylophilus. Responses varied with plant material and concentration. Good nematicidal activity against male, female and juvenile nematodes of B. xylophilus was achieved with essential oils of Cinnamomum verum, Leptospermum petersonii, Asiasarum sieboldi, Boswellia carterii, Pimenta racemosa, Cymbopogon citratus, Mentha spicata, clove and garlic. Garlic and cinnamon oils showed the most potent nematicidal activity among the plant essential oils. Analysis by gas chromatography-mass spectrometry led to identification of three major compounds from garlic and two from cinnamon oil. These five compounds from two essential oils were tested individually for their nematicidal activities against the pine wood nematode. Responses varied with compounds and dose. LC50 values of diallyl trisulphide, diallyl disulphide and cinnamyl acetate against juvenile nematode were 2.79, 37.06 and 32.81 μl−1, respectively. The essential oils described herein merit further study as potential nematicides against the pine wood nematode.