Abstract: The huge flood along the Changjiang River is the catastrophic flood of the whole basin along the Changjiang River. The huge flood along the Changjiang River is a result of the comprehensive action of the various physical factors. Now it is demonstrated that the physical factors which play a main part in the huge flood along the Changjiang River are as follows: monsoon of Asia, subtropical high of the west Pacific Ocean, blocking high of the middle latitude, snow on the Qinghai-Xizang Plateau in winter season, El Nino event, sunspot activity and so on. The physical factors which play a next part in the huge flood along the Changjiang River are as follows: assemble of nine stars, trade wind, earth’s rotation rate, geothermal release, eclipse of the sun and so on. The concept of composition of the physical factors before the huge flood along the Changjiang River is put forward. Before every huge flood arises, there are generally the similar characteristics that are some inherent compositions between the main physical factors that have an effect on the huge flood. That is, in next year of El Nino event around the transformation year of magnetic cycle of sunspot activity, the position of subtropical high of the west Pacific Ocean in summer changes south because of the influence of sunspot activity and El Nino event. At the same time, excessive snow on the Qinghai-Xizang Plateau decreases thermal action of the plateau, and blocking high of the middle latitude changes south frontal zone south. Because monsoon of Asia become weaker by them, the position of main rain band of China in summer changes south. Hence the catastrophic flood of the whole basin arises along the Changjiang River. These compositions are strong signal of the huge flood along the Changjiang River, which is of important indication function for forecast research of the huge flood along the Changjiang River.