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Two cores were recovered from raised peat bogs on the tropical northern Leizhou Peninsula, south China. Multiple sediment variables including organic matter (OM) content, the stable carbon isotope signature of OM, low-frequency magnetic susceptibility and degree of humification, indicate that the regional paleoclimate played an important role in determining the nature of peat that accumulated. Based on comparison with other climate proxies, the bulk peat delta C-13 record was interpreted as an indicator of variation in the East Asian (EA) summer monsoon, and to a lesser extent, the Indian summer monsoon, during the last glacial period between similar to 49 and 10 cal ka BP. More negative bulk delta C-13 values reflect wetter and warmer conditions, and thus a strong EA summer monsoon. More positive values indicate drier and cooler conditions. A warm and wet period occurred between similar to 46 and 28 cal ka BP, implying a strengthening of the EA summer monsoon. A climate shift occurred at similar to 22 cal ka BP and the driest and coldest period appeared between similar to 19 and 16 cal ka BP, suggesting weakening of the EA summer monsoon. After similar to 12 cal ka BP, climate shifted towards wetter and warmer conditions again. It has been suggested that variations in orbitally induced solar insolation played a role in the last glacial climate of the study region. Several millennial-scale arid and cold phases characterized by C4 plants, or by more positive delta C-13 values during periods when C3 plants dominated, show agreement with the Greenland GISP2 ice core and the Chinese stalagmite records. Interactions between high northern latitude cold air advection and summer moisture transported across the tropical ocean, and the migration of the mean position of the Intertropical Convergence Zone (ITCZ) would have favored these millennial-scale phases. Additionally, changes in heat transport to the North Atlantic would also have influenced climate in the region.