Abstract: The transducer-focusing system is the most important part in a scanning acoustic microscope. We proposed and developed a new type of such system-glass-motal based concave spherical transducer. Compared with Quate's plain transducer-simple lens system and Chubachi's gold cup based concave transducer, there are some unique advantages in our new system. The scattered acoustic field outside the lens is avoided, higher resolution is obtained more easily, and the structure and technology of our new system are appropriate for frequencies up to GHz range. The structupe, material and technology of the metal-glass based concave transducer are described, and the theoretical analysis as well as the experimental results are presented.