Joint Center for Advanced High Performance Computing (JCAHPC) decided to introduce its new supercomputer system (Post T2K system) with 25 PFLOPS peak performance. The new system is named “Oakforest-PACS” with 8,208 of next-generation manycore processors developed by Intel Corporation, and is planned to start its full operation on December 1st, 2016. The Oakforest-PACS will be the fastest supercomputer system in Japan at that time.