Ultrasound is a mechanical vibration wave with frequencies above 20 kHz, which has mechanical effect, heating effect and cavitations effect. The ultrasound with different intensity has been applied for organisms tissues and cells with different biological effects. With the development of engineering technology, ultrasound has been widely applied to medical imaging, solid tumor treatment and other directions in biomedicine. Low intensity ultrasound has gradually been considered as an important engineering tool to assist the stem cell therapy of various diseases. The detailed understanding of ultrasound for stem cell therapy will promote further application of ultrasonic technology and the development of clinic applications. The progress of ultrasound for stem cell therapy is introduced in this review, including promoting stem cell proliferation, differentiation and migration, tracking stem cell by ultrasound image and target drug delivery. Finally, ideas about improving ultrasound for stem cell therapy in future are discussed.