The invention discloses a harmaline oxazoline compound and a preparation method and application thereof .The structural formula of the harmaline oxazoline compound is shown as the formula (I) in the description, wherein in the formula (I), R1 is methyl or phenyl or p-chlorophenyl or o-hydroxybenzyl, and R2 is o-hydroxybenzyl or 3-methoxy-4-hydroxyphenyl or 3,5-dimethyl-4-hydroxyphenyl or 2-furyl .The compound has significant cytotoxic activity on spodoptera frugiperda cultured cell lines Sf9, has good insecticidal activity on culex fatigans and lipaphis erysimi, has good growth and development regulating activity on prodenia litura, and also has good inhibitory activity on rhizoctonia solani, colletotrichum gloeosporioides, phytophoria melonis, fusarium oxysporum f .sp .niveum, pseudoperonospora sp, botrytis cinerea and fusarium oxysporum f.sp.cubense .Besides, the compound is simple in structure, easy to synthesize, simple in synthetic process, high in product purity and suitable for large-scale industrial application and popularization.