This proposal is about a project to study the biological activities of Artemia caused by ultrasound exposure. Ultrasound is employed clinically, for example, in medical diagnosis as a pulse-echo technique for obtaining information of tissue characteristics. It can also use the high-intensity-ultrasound to destroy the lump and pathogens of human tissues. In the other hand, the ultrasonic experiments of plant or insect tissues that contain gas in intercellular channels irradiate with megahertz frequencies of ultrasound, causing perturbation and destruction in nearby cells. Thus, the ultrasonic biological effect, in general, is destructive. However, ultrasound can be a noninvasive form of mechanical energy propagated in biologic organisms. This fact attracts our attention to identify the biologic mechanisms corresponding to the biological activation of Artemia induced by ultrasound exposure. To perform the above-mentioned research, the oscillation of the Artemia in response to the ultrasound radiation is simulated using Rayleigh-Plesset¡¦s bubble activation theory. The gas body activation theory is to calculate the resonant frequencies of the Artemia at different stages of its life. The calculated resonant frequency range of the Artemia cyst shape and the embryonic cuticle is about 0.222~0.226 MHz and 2.46~4.71 MHz. By using the above mentioned resonance frequency of the Artemia, the maximum relative growth rate was increasing 16%. It was found that the Artemia of activation and increasing the hatching rate appeared during irradiation.