Stable oxygen and carbon isotope records from ODP Site 1143 (9 degrees C21.72'N, 113 degrees C7.11'E, 2772 m) in the southern South China Sea (SCS) are presented for benthic foraminifers Cibicidoides wuetlerstorfi and Uvigerina peregerina in 64 samples. The results show that the average difference in delta (super 18) O between Cibicidoides wuellerstorfi and Uvigerinaperegerina in 64 samples from Site 1143 is (0.614+ or - 0.07) X 10 (super -3) , close to 0.64 X 10 (super -3) , the standard oxygen isotope difference between the Atlantic and the East Pacific. Results show the average delta (super 13) C difference between these two species at Site 1143 is (0.692 + or - 0.04) X 10 (super -3) , much lower than 0.9 X 10 (super -3) , the standard carbon isotope difference between the Atlantic and the East Pacific. The lower difference in delta (super 13) C at Site 1143 may be due to low productivity in reef areas which decreased the delta (super 13) C difference between depositions and sea water. This test at Site 1143 provides an adjustable standard for oxygen and carbon isotope values between the benthic foraminifera Cibicidoides wuellerstorfi and Uvigerina peregerina for paleo-oceanographic studies in the South China Sea and even in the West Pacific.