In　order　to　study　the　variability　of　the　upper　sea　temperature　in　the　tropical　Pacific　and　Indian　Oceans　and　reveal　their　coupling　relationship　with　East　Asian　summer　monsoon　circulation,　the　singular　value　decomposition　is　employed　to　reveal　the　variation　of　120　m　sea　temperature　in　the　tropical　Pacific　and　Indian　Oceans,　the　main　modalities　of　anomalous　activities　of　the　East　Asian　summer　monsoon,　and　their　mutual　relation.　The　results　show　that　during　the　summer　of　years　with　strong　summer　monsoon,　the　western　Pacific　subtropical　high　is　weak　and　its　location　is　northerly.　In　years　with　strong　summer　monsoon,　the　sinking　movement　of　vertical　velocity　anomalies　in　East　Asia　weakens　the　Meiyu　front　and　vice　versa.　When　the　850　hPa　east　trade　winds　in　the　equatorial　central　and　eastern　Pacific　Ocean　are　enhanced,　the　middle　Indian　Ocean　and　the　western　Pacific　Ocean　show　westerly　anomalies.　Meanwhile,　if　the　meridional　wind　anomalies　on　both　sides　of　the　equator　in　the　central　Indian　Ocean/　eastern　Pacific　and　East　Asia　show　a　clear　convergent　and　divergent　pattern,　respectively,　the　corresponding　120　m　sea　temperature　shows　a　La　Nina　state　and　is　easy　to　trigger　the　strong　East　Asian　summer　monsoon.