The shock-induced collapse and jet formation of a single air bubble inside a cylinder filled with gelatin and an artificial thrombus were investigated using high-speed photography. A thrombus was prepared in vitro and inserted in a cylinder modeling an artery to establish a treatment for brain embolism by the interaction of an underwater shock wave with an air bubble. When the shock wave was applied to an air bubble of mm in diameter, the liquid jet that formed within the bubble penetrated the thrombus. Liquid jet impact ablation of the for thrombus was found to be very effective, and provided valuable information for the treatment of brain embolism.