Petroleum Energy Center of Japan has been carrying out a 7-year development program to prove the potential of an automotive ceramic gas turbine for five years with the support of the Ministry of International Trade and Industry. The ceramic gas turbine now under development is a regenerative single shaft engine. The output is 100kW, and the turbine inlet temperature (TIT) is 1350°C. All the ceramic components are now entering the 1350°C TIT test phase after completing 1200°C TIT evaluation tests, including durability tests, in various types of test rigs. The compressor-turbine combined test rig and the full assembly test rig which is the same as an actual engine and incorporates all the components are now going through 1200°C TIT function and performance evaluation tests. In the near future, we are planning to increase the TIT to 1350°C. In consideration of the current level of high-temperature, long-term strength available from the ceramic materials, we decided to change the rated speed to 100,000 rpm because the initial rated speed of 110,000 rpm, if unchanged, involves considerable risks. Then we reviewed mainly the designs of the compressor and turbine and revised the target values of the individual components to match the specifications that satisfy the target performance of the engine.