ultrasound assisted extraction intensifies the kinetic of the extraction process by acting upon the interfacial area, though the disintegration of particles. compared with batch extraction, it improves the extraction process decreasing both extraction time and temperature while increasing the rate of extraction. UAE technique was used to obtain active principle aloin from a herbal plant Aloe Vera. Methanol was selected as organic solvent as found maximum extraction of aloin with it. the active principle aloin was quantified using WATER's HPLC system. The optimum extraction conditions were estimated as extraction temperature, extraction time and dry gel loading. Effective intraparticle diffusivity of aloin in methanol soolvent was estimated using unsteady state mass diffusion model, and activation energy of diggusionn using Arhenius equation respectively