Objective To explore the application value of Jatropha curcas， preliminary study on insecticidal and antibacterial activities of the crude extracts from the alkaloids of Jatropha curcas L. was carried out．Method Two major agricultural pests （cabbage aphid, cabbage green worm) and three pathogens （pomegranate dry rot, apple rot and strawberry gray mold) in Panxi area were used as experimental materials to determine the insecticidal and bacteriostatic activities of crude alkaloid extracts from Jatropha curcas L.by dripping method and growth rate method.Results In terms of insecticidal activity, the crude extract of Jatropha curcas L. alkaloids had high contact activity against homoptera cabbage aphids and lepidoptera cabbage caterpillars. The LC50 values ranged from 42.247 8 to 46.249 7 mg / L, and the LC90 values ranged from 331.714 0 to 342.491 7 mg / L, which was generally equivalent to the insecticidal effect of 2.5 % deltamethrin EC.； In terms of inhibiting pathogenic fungi， the EC₅₀ of the crude extract of Jatropha curcas Alkaloids against pomegranate dry rot， apple rot and strawberry gray mould were 70.635 5， 52.400 6 and 133.412 2 mg/l respectively， and its antibacterial effect was better than that of the control agent 50% carbendazim WP to a certain extent.Conclusion In conclusion， the extract of Jatropha curcas L. has strong insecticidal and bacteriostatic effects， and has good application prospects in the development of botanical pesticides.