Abstract: The shell structure is developed for the Undersea Data Center to isolate it from seawater and dissipate the heat generated by the data center. With the help of gasbags and a gantry crane the shell can bring the data center up for routine service. In emergency, the shell itself can bring the data center up to sea surface. The shell structure is optimized for high heat dissipation efficiency and comfortable working condition. Simulations are conducted to examine the performances of the shell, including the surface stress of the shell, deformations under various working conditions and total heat dissipation.