Because of an emerging importance of clean energy, fuel cells are attract more attention due to their ability to produce high efficient power without any harmful emission. Fuel cells are energy conversion device with directly convert chemical energy into electrical energy by the chemical reactions, which have potential applications in automobile, spacecraft, stationary, industrial and home appliances. Recently there are gaining demand to develop an intermediate temperature fuel cell and available proton conductors at $200{sim}500^{circ}C$, which promising operating temperatures range for both material science and energy conversion processes. In this paper, we have reviewed electrochemical properties and current technology of solid state proton conductors. In addition, development of intermediate temperature fuel cell using the perovskite-type solid protonic conductor is also discussed.