Drug-loaded microbubbles ultrasound contrast agent is a new diagnostic reagents which can be effectively targeted to some textures,can load the drugs and can release drugs controllably so that it can be used in the diagnosis and therapy of many diseases.But the microbubbles made by existing technologys have poor stability,incomplete drug release,and low drug entrapment efficiency.This paper reports a triphase drug-loaded microbubble fabrication method using a simple and novel capillary inserted three-phase microfluidic chips,which can precise control fluid,to improve the size uniformity,the drug entrapment efficiency and the microbubble stability.We have prepared some molds by DuPont dry and the corresponding PDMS chips which produced by those molds have been used in microbubble preparation experiment.Using DuPont dry technology,we did a threedimensional design for the channel convergence department so that we can get a very small nozzle.We introduced an aqueous phase,an oil phase containing phospholipids and drugs,and a gas phase containing trifluoropropane into the 3D microfluidic chip.Under the effect of surface tension,a phospholipid shell with oil phase membrane containing a gas core is spontaneous formatted as a microbubble ultrasound contrast agent.Now we have produced microbubbles which have uniform size and low diameter.Its diameter could be controlled under 5μm.The factors on size of microbubbles,such as water velocity,gas pressure and oil velocity,have been explored.The recipe of phospholipid and fatty acid,oil film thickness,and preparation temperature has been optimized to implement the preparation of microbubbles with a phase transfer from liquid to solid of the microbubble shell.And thhe stability of microbubble shell membrane has been improved successfully.