We adopt the soakage extracting method and ultrasonic extracting method to extract insecticidal and antimicrobial active ingredients from Artemisia sieversiana, Artemisia annua and Artemisia scoparia. The result show that the best solvent for extraction is 95% ethanol solution for these three species of Artemisia, the best extraction method is ultrasonic extracting method. The lethal concentrations in the contact toxicity of the three species of Artemisia extracts to the 3rd instar larvae of Lymantria dispar were 6.0392, 7.6075 and 11.2561mg/ml. It also has antibacterial effect on Fusarium sporotrichioides, Cytospora chrysosperma, Guignardia laricina and Bipolaris maydis. And the inhibition ratio of growth of the four kinds of pathogenic fungal hyphae is over 50%, when the solution concentration is ≥ 40mg/ml.