Several kinds of ionic liquids with different cations and anions were applied for ultrasonic-assisted extraction [1] of astaxanthin from shrimp waste [2].One amino-imidazolium ionic liquid in ethanol with 0.50 mol/L was selected as the solvent.At the optimized ultrasonic extraction conditions,the extraction amount of astaxanthin increased 98% compared to the conventional method.Subsequently,the extracted solution was isolated by the molecularly imprinted solid phase extraction.After loading the samples on molecularly imprinted polymer cartridge [3],the different washing and elution solvents were evaluated,and finally astaxanthin was separated from the interferences in shrimp waste extract successfully.