Abstract: The 30-60-day low frequency summer monsoon motion in Indonesia-Northern Australia during the period of November of 1981 to March of 1982 and its relationship to the general circulations in both Southern and Northern Hemispheres, based on the data from ECMWF/WMO and the data of outgoing longwave radiation (OLR) provided by the polar orbit satellite NOAA, have been studied by employing a method of extended empirical orthogonal function (EEOF).The result shows that the 30-60-day low frequency northeast (southwest) wind flowed from the coastal area of East Asia at 850 hPa could be turned to a low frequency summer monsoon northwest (southeast) wind in Indonesia-Northern Australia as it moves southwards across the equator. The convection (drought) over the area prevailing summer monsoon air is enhanced and then stretches eastwards when a convergence occurs since the low frequency summer monsoon northwest (southeast) wind meets the strengthened low frequency southwest (northeast) wind in Western Australia. addition, the pattern of the low frequency geopotantial hight fields at 850hPa is well coordinated.These outcomes of investigation are similar to that one based on the practical data of radius filtering, thereby illustrating that the component of the low frequency variation tropical general circulation variation.