The Okinawa Trough is an initial back arc basin developed on the continental crust due to the subduction of Philippine Sea plate under Eurasian plate. It is a natural laboratory to study the basin evolution, magmatism and crust-mantle interactions in the early stage of back arc expansion. Although a lot of investigations and research works have been done so far, there are still some controversial or urgent scientific problems, such as the genetic relationship between acid pumice and basic basalts in the trough, the control of tectonic background on magmatism in different sections of the trough, the characteristics of magma-derrived mantle, and the influence of subduction plate components (fluid + melt) on the mantle wedge, etc. On the basis of systematically collecting and sorting out (excluding some doubtful data) the major element, trace element (including rare earth elements) and Sr-Nd-Pb isotopic data of volcanic rocks in the Okinawa Trough, the author further confirmed the magma homology of acid pumice and basic basalt through systematic analysis of the data, and believed that the distributions of acid pumice and neutral andesite in the north and middle sections of the trough should be the reflection of regional rift at present, while the basic basalts widely distributed in the south section indicate that they are close to mature back arc basin in structural property. The volcanic magma source area of Okinawa Trough has the characteristics of enriched mantle II (EMII)-type Dupal anomaly, and the magma comes from the source mixed by end-member of prevalent mantle (PREMA) and EMII type mantle end-member, of which the ratio of EMII is about 15% and PREMA about 85%. The addition of fluid/melt from subducted Philippine Sea plate (subducted ocean crust or sediment) is the reason for the EMII type characteristics of magma-derrived mantle beneath the Okinawa Trough, which is different from the viewpoint that the Dupal anomaly originates from the interaction between crust and mantle.