Abstract: The SST of Pacific and Indian Oceans has been studied through the analyses of EOF. It has been found that the distribution of SST anomaly appears to be clear reversed changes between Northwest Pacific and Southeast Pacific as well as that between Northwest Pacific and Arabian Sea. It is also found that SLP anomely between North Pacific and North Indian Ocean is of a phenomenon of seesaw distribution called North Pacific and North Indian Ocean Oscillation (PIO). The phenomenon has a great influence on cold summer in East Asia.