A nematocide containing lactonic ring and a preparation method and application thereof. The nematocide containing lactonic ring includes hydrogen, cyan, fluorine, chlorine, bromine, alkyl containing 1 to 4 carbon atoms, alkoxy containing 1 to 4 carbon atoms, alkoxyphenyl, alkoxy containing 1 to 4 carbon atoms and one or more chlorine atoms in place of hydrogen atoms on the carbon atoms, alkoxy containing 1 to 4 carbon atoms and one or more fluorine atoms in place of hydrogen atoms on the carbon atoms, nitryl, and amido; R6 is selected from hydrogen, fluorine and chlorine. A result is good control effects on the eggs and second-stage juveniles of root-knot nematodes, and especially inhibition of the hatch of root-knot nematode eggs on cucumbers, tomatoes, tobaccos and soybeans, etc. The nematocide has high insecticidal efficacy and can prevent the production of antibodies in pests even after a long time of use.