Ocean Drilling Program (ODP) Site 1144 is located in the northern South China Sea (SCS). The age at a core depth of 517 m is about 1.0 Ma BP. Of all the physical property measurements, color reflectance (CR) data have the highest resolution, with an average value of <60 years (sometimes better than 10 years). Therefore, it is the ideal indicator for studying millennial-scale climate changes. Wavelet and cross-frequency analysis has let us know that in obliquity cycles, changes in CR and in oxygen isotopes of plankton Foraminifera are similar to each other, and eccentricity has been dominant for the last 700,000 years. Like the GISP2 ice records of Greeland, CR changes in the SCS also recorded D/O-like events. 3 ka and 1.5 ka periods were revealed through wavelet analysis of CR; they occurred not only in glacial periods (such as MIS 2-4, 6, 8), but also in interglacial periods (such as MIS 15, 17, 19, 25, etc.) and in terminal periods (such as MIS 11/12, 15/16). These signals have been much stronger in glacial periods than in interglacial periods over the last 700,000 years. This not only indicates the instability of the climate throughout the glacial/interglacial cycles, but also the climate transformation in the middle Pleistocene.