For the aim of screening nematicidal materials, Bursaphelenchus xyluplilus and Meloidogyne incognita were used as target in vitro bioassay to determined nematicidal activity of oil-tea cake and other plant materials; further control effects of tea-saponin preparations and oil-tea cake were assessed against root-knot nematode disease in pot experiment and field experiment, respectively. The results showed that plant extracts of oil-tea cake, tea-pericarp, and tea-seed reached strong nematocidal activity, inducing 90, 100 and 100% mortality of B. xyluplilus respectively at 10 mg/ml after exposure for 72 h. Plant extracts of oil-tea cake and tea-seed reached medium-strong activity against M.incognita after exposure for 48 h. The effects of plant extracts concentrations on toxicity against B.xyluplilus were observed. The tea-saponin preparations obviously controlled tomato root-knot nematode disease in pot experiment, root gall, and M. incognita juvenile 2 (J2) population were reduced; tomato biomass were increased obviously at 30 d after pot-soil treated with 1.5 g and 0.75 g (effective content) tea saponin per 1 kg soil at tomato seedling transplant. Oil-tea cake showed certain effect against root-knot nematode disease in field experiment applied by furrow application one week before Fructus Trichosanthis emergence, and the proliferation of J2 in soil was inhibited significantly 150 d later, while the fruit number and diameter were increased 180 d later after application. This paper reported the pot and field control effects of oil-tea vice products against plant nematodes for the first time. The results provide a basis for directly using oil tea and tea vice-products to the control of crop root-nematode disease.