In gene therapy, it is important to develop an effective and safe gene delivery system. Especially, from the viewpoint of reducing side effects, gene delivery into a specific site is essential. We previously, developed liposomal bubbles (Bubble liposomes) containing perfluoropropane. Bubble liposomes were useful as ultrasound enhanced gene delivery tools in vitro and in vivo. In this review, we introduced the characteristics of Bubble liposomes as ultrasound imaging agents and ultrasound enhanced gene delivery tools. Bubble liposomes worked as ultrasound imaging agents in cardiosonography. In addition, their combination with ultrasound exposure was able to deliver plasmid DNA in the femoral artery. The gene expression was only observed at the site of ultrasound exposure. Moreover, the gene delivery by Bubble liposomes and ultrasound exposure was more efficient than that by conventional lipofection method using Lipofectamine 2000. Therefore, it was suggested that Bubble liposomes might be a new class of tools for site specific gene delivery.