Abstract: Hydrogen gas (H2) is a novel, simple and safe antioxidant. However, its poor solubility in water, the difficulties to track by imaging and to be released in a controllable manner limit its bio-medicine application. Microbubbles (MBs) are ideal ultrasound contrast agents and can be used as the ultrasound-activated drug carriers. In this work, hydrogen-loaded microbubbles (H2-MBs) were prepared and their performance in ultrasound imaging in vitro and in vivo were examined. Experiment results showed that H2-MBs have excellent ultrasound imaging capability both in phosphate buffered saline and in the rat left ventricular and liver. The study provided a novel H2 formulation and laid the foundation for further H2 therapy application.